JSON Schema generator from sample JSON
Infer a Draft-07-compatible JSON Schema from sample JSON, then copy or download it.
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Infer a Draft-07-compatible JSON Schema from sample JSON, then copy or download it.
Use →Build a DMARC DNS TXT record from policy, aggregate-report address, percentage, and alignment settings.
Open →Build an SPF TXT value from sending IPs, include domains, a/mx mechanisms, and an all policy.
Open →Generate CAA record lines for permitted certificate authorities and optional iodef reporting.
Open →Split long TXT values into 255-character chunks and format them for DNS configuration.
Open →Draft an llms.txt file from a site name, summary, and key pages. It is guidance metadata, not access control.
Open →Generate robots.txt blocks for selected AI crawler user agents with allow or disallow rules.
Open →Build an X-Robots-Tag HTTP header value from noindex, nofollow, nosnippet, and preview directives.
Open →Build a Strict-Transport-Security header from max-age, includeSubDomains, and preload options.
Open →Calculate the pixel dimensions required for a physical print size at 300 DPI.
Open →Calculate the pixel dimensions required for a physical print size at 350 DPI.
Open →Calculate the pixel dimensions required for a physical print size at 600 DPI.
Open →Calculate A4 pixel dimensions (210 × 297 mm) at any DPI, in portrait or landscape.
Open →Convert pixel dimensions and DPI into physical print size in millimetres and inches.
Open →Pick one name randomly with probability proportional to a weight you assign to each entry.
Open →Draw names one at a time without repeating a name until the list is reset.
Open →Select multiple unique names at random from a list in one draw.
Open →Shuffle a list into a random order and return a numbered sequence.
Open →Draw multiple unique integers from a range without replacement.
Open →Estimate file transfer time from file size, throughput, latency and an estimated number of round trips.
Open →Estimate upload duration from file size and upstream speed.
Open →Enter file size and download speed to see how long the download will take.
Open →Estimate local file copy time from data size and effective transfer speed in MB/s.
Open →Estimate migration duration from data volume, throughput and an effective utilization percentage.
Open →Add N business days to a start date while skipping weekends and optional excluded dates.
Open →Subtract N business days from a date while skipping weekends and optional excluded dates.
Open →Convert a business-day range such as 3–5 days into earliest and latest calendar dates.
Open →Convert RGB values (0–255) to HSL hue, saturation and lightness.
Open →Convert HSL hue, saturation and lightness into RGB values (0–255).
Open →Convert RGB values (0–255) into a #RRGGBB hexadecimal color code.
Open →Convert #RGB or #RRGGBB hexadecimal colors into RGB values.
Open →Parse a URL into protocol, host, port, path, query parameters and fragment.
Open →Parse a raw HTTP request into request line, headers and body without sending it.
Open →Parse an ISO 8601 datetime and convert it to UTC, local time and Unix timestamps.
Open →Convert a WebP image to PNG locally in your browser and download the result.
Open →Test JavaScript regular expressions with flag checkboxes, highlighted matches, indexes, capture groups, named groups, and replacement previews.
Open →Convert markup percentage on cost into gross margin percentage on selling price.
Open →Find blank or over-130-character product names in a Mercari Shops bulk registration CSV.
Open →Find product descriptions longer than the documented 3,000-character limit before Mercari Shops import.
Open →Validate Mercari Shops condition codes as the documented numeric values 1 through 6.
Open →Validate Mercari Shops shipping method codes as the documented numeric values 1 through 6.
Open →Check that Mercari Shops inventory delta flags (1/2) and positive delta quantities are paired correctly.
Open →Warn when new BASE product rows leave price, stock or publication fields blank and therefore rely on defaults.
Open →Validate Shopify product CSV Status values as active, draft or archived.
Open →Check Shopify Inventory tracker values and flag entries outside the documented/common values.
Open →Validate Continue selling when out of stock as deny, continue or blank/default.
Open →Check integer gram weight values and display units g, kg, lb or oz in Shopify product CSV files.
Open →Check standard fulfillment values and the lowercase-hyphen syntax for custom fulfillment service handles.
Open →Check that rows updating SKU, barcode, weight or inventory also include the required Option1 name/value context.
Open →Validate WooCommerce Published values as 1, 0, -1, 2, true or false.
Open →Validate WooCommerce catalog visibility values as visible, catalog, search or hidden.
Open →Validate WooCommerce Tax status values as taxable, shipping or none.
Open →Check WooCommerce In stock?, Stock and Backorders allowed? values before import.
Open →Check regular/sale prices, weight and dimensions for plain numeric values before WooCommerce import.
Open →Split WooCommerce Images entries and validate external image URLs and whitespace before import.
Open →Validate Merchant Center price values in number + 3-letter currency format, such as 15.00 USD.
Open →Validate availability values and require availability_date context for preorder/backorder rows.
Open →Validate Merchant Center condition values as new, used or refurbished.
Open →Normalize spaces/dashes and validate 8, 12, 13 or 14-digit GTINs and their GS1 check digit.
Open →Validate yes/true/no/false and warn about obvious conflicts with GTIN, MPN and brand fields.
Open →Check required title/description values and the 150/5,000-character limits in a Merchant Center feed.
Open →Check whether a Mercari Shops CSV decodes cleanly as Shift_JIS or UTF-8 before upload.
Open →Find half-width spaces outside product name and description fields, a documented Mercari Shops import error cause.
Open →Validate Mercari Shops SKU management codes and JAN values for documented length and character rules.
Open →Count product rows and flag CSV files that exceed the documented 10,000-product bulk registration limit.
Open →Check a BASE image ZIP for nested folders, non-ASCII filenames and the 1 GB batch limit before import.
Open →Check BASE product CSV variation names for duplicates within a product and values longer than 255 characters.
Open →Count STORES inventory CSV rows and flag uploads that exceed the documented 5,000-item limit.
Open →Find duplicate variation IDs in a STORES inventory CSV before upload.
Open →Validate STORES inventory update values as integers from 0 to 9,999 or the supported unlimited value.
Open →Count columns per row and flag ColorMe CSV rows that do not match the documented 59-column registration or 60-column update formats.
Open →Detect malformed quoting and row-width changes caused by commas, newlines or double quotes in ColorMe CSV files.
Open →Find duplicate product handles and handle rows without titles before Shopify CSV import.
Open →Detect duplicate option-value combinations within the same Shopify product handle before import.
Open →Check UTF-8 encoding and malformed CSV quoting that can trigger Shopify “Illegal quoting on line” errors.
Open →Check WooCommerce variation rows for duplicate SKUs, missing Parent references and missing attribute values before import.
Open →Check core Google Merchant Center feed attributes, availability values and price syntax before upload.
Open →Check encoding, headers, length limits, spaces and required values before importing a Mercari Shops product CSV.
Open →Read a Mercari Shops product_import_result CSV and group common import errors by row.
Open →Check image formats, the 8 MB per-image limit, 1 GB batch size and duplicate filenames before bulk upload.
Open →Check product IDs, SKU IDs and multi-column requirements for inventory and image updates before upload.
Open →Check image name and URL columns for spaces, URL syntax, extensions and duplicates before import.
Open →Match image filenames referenced by a BASE product CSV against a ZIP archive and find missing or risky filenames.
Open →Check blank product/variation IDs and stock-field combinations that can create new products or fail updates in BASE.
Open →Check the 5,000-item limit, duplicate variation IDs and invalid stock values before a STORES inventory CSV upload.
Open →Check UTF-8, required fields, prices, fulfillment values, duplicate options and image URLs before Shopify import.
Open →Check Shopify Image Src values for http/https syntax, spaces, duplicates and obvious non-direct links.
Open →Check UTF-8, required names, duplicate SKUs, product types, statuses, parents and images before WooCommerce import.
Open →Check image_link values in a product feed CSV for URL length, scheme, ASCII, supported image formats and unencoded characters.
Open →Check product create/update CSVs before upload.
Open →Check encoding, price, stock and duplicate values before import.
Open →Check the customer import format and common field errors.
Open →Check the option CSV, name/item order and numeric fields.
Open →Validate Timestamp, Person//Email / ID and $event_id before import.
Open →Check identifiers, duplicates and the 50 MB limit before list import.
Open →Check headers, email, phone, address fields and encoding before upload.
Open →Check encoding, delimiter, CSV syntax and signs of Excel tab conversion.
Open →Inspect likely encoding and comma, tab, semicolon or pipe delimiters.
Open →Find tab conversion, scientific notation and date-like coercion after Excel edits.
Open →Compare header names, order, missing columns and extra columns.
Open →Find duplicate values and row numbers in a selected column.
Open →Split a large CSV into files with a chosen number of rows.
Open →Merge multiple CSV files with matching headers.
Open →Find emoji and special characters that often cause problems in Shift_JIS-based imports.
Open →Convert between CSV and tab-separated text in your browser.
Open →Check timestamps, cue order, start/end times and basic subtitle errors.
Open →Check VCALENDAR / VEVENT structure, UID, DTSTART and basic fields.
Open →Convert Japanese era dates and Gregorian dates line by line.
Open →Normalize Japanese phone numbers and convert between domestic and +81 forms.
Open →Draw a lighthearted fortune and lucky action for today.
Open →Let a playful oracle answer a simple yes-or-no question.
Open →Pick one lunch option at random.
Open →Pick one name or item at random.
Open →Shuffle names into a chosen number of teams.
Open →Create a randomized numbered seating order.
Open →Draw a conversation topic for friends, family or a casual date.
Open →Draw a harmless, lighthearted game penalty.
Open →A playful unofficial compatibility gacha for two four-letter types. Not a psychological assessment.
Open →Choose a four-letter type and draw a playful message for today.
Open →Count characters, spaces, word-like segments, lines, paragraphs, UTF-8 bytes, and Unicode code points in real time, with optional filters and local snapshots.
Open →Remove duplicate lines while keeping the first occurrence.
Open →Sort lines ascending, descending, or by length, with optional natural ordering, locale, sensitivity, trimming, blank-line removal, and deduplication.
Open →Compare two texts line by line and show additions / removals.
Open →Percent-encode or decode URL text.
Open →Format or minify JSON, locate syntax errors by line and column, choose indentation, optionally sort keys, inspect structure metrics, and copy or download the result.
Open →Encode or decode Unicode text as Base64.
Open →Convert Unix seconds / milliseconds and human-readable dates.
Open →Calculate final price and savings from a discount rate.
Open →Calculate percentages, percentage values and change rates.
Open →Solve proportions, simplify ratios, and normalize values around 1.
Open →Calculate age from a birth date and target date.
Open →Calculate the difference between two dates in days and weeks.
Open →Generate one UUID v4 or RFC 9562 UUID v7 locally in the browser.
Open →Generate SHA-256 / 384 / 512 hashes locally in your browser.
Open →Convert HEX or RGB colors to HEX, RGB and HSL.
Open →Generate random passwords locally with chosen character sets.
Open →Turn a title or phrase into a URL-friendly slug.
Open →Convert text to upper, lower, title, snake, kebab or camel case.
Open →Shuffle input lines into a random order.
Open →Draw random numbers within a chosen range.
Open →Estimate total book/zine weight from trim size, pages, paper gsm and quantity.
Open →Estimate shipping box count from total item volume and box dimensions.
Open →Calculate dimensional weight with a configurable carrier divisor.
Open →Calculate document size including bleed from final trim dimensions.
Open →Convert physical print size and DPI into required pixel dimensions.
Open →Calculate full cover spread size including spine and bleed.
Open →Calculate physical sheet count from page count.
Open →Check whether booklet page count is a multiple of 4.
Open →Estimate spine width from page count and custom sheet thickness.
Open →Check whether display elements fit across a convention table.
Open →Calculate how many products fit in a display grid.
Open →Estimate a practical cash float from prices and expected cash sales.
Open →Calculate units needed to break even on an event.
Open →Calculate convention/event profit and margin.
Open →Split total inventory across event days using custom weights.
Open →Calculate bundle price and savings from item prices and target discount.
Open →Estimate return shipping boxes for unsold books.
Open →Turn rough notes into a categorized convention packing checklist.
Open →Check page filename lists for missing or duplicate sequence numbers.
Open →Calculate how many price tags fit on one print sheet.
Open →Compare two products by unit price.
Open →Calculate gross profit, margin and markup.
Open →Convert tax-inclusive and tax-exclusive prices with a custom rate.
Open →Calculate required hourly rate from target monthly income.
Open →Calculate net working time from start, end and break.
Open →Calculate business days between two dates with optional Japanese holidays, custom working weekdays, endpoint inclusion, and custom closure dates or ranges.
Open →Add or subtract days/weeks from a date.
Open →Calculate elapsed time between two clock times, including overnight.
Open →Scale recipe quantities for a different serving count.
Open →Estimate fuel cost from distance, efficiency and fuel price.
Open →Estimate electricity cost from wattage, hours and kWh rate.
Open →Enter file size and transfer speed to estimate how long the transfer will take.
Open →Convert decimal and binary storage units.
Open →Simplify an aspect ratio and calculate matching dimensions.
Open →Calculate resized dimensions while preserving aspect ratio.
Open →Generate a fluid CSS clamp() expression from viewport and size ranges.
Open →Build a URL with standard UTM parameters.
Open →Generate a mailto link from recipient, subject and body.
Open →Parse URL query parameters into a readable list.
Open →Generate TOTP codes locally from a Base32 secret or otpauth:// URI.
Open →Decode JWT header and payload locally. Signature is not verified.
Open →Recursively sort JSON object keys alphabetically.
Open →Remove duplicate values/objects from a JSON array.
Open →Format and validate XML in the browser.
Open →Generate a Markdown table from tab- or comma-separated rows.
Open →Extract lines that appear in both lists.
Open →Extract lines unique to list A or list B.
Open →Find and replace text using literal or regular-expression matching, with flags, replace-all or first-only scope, case options, and match-count preview.
Open →Add the same prefix and suffix to every line.
Open →Extract selected columns from pasted CSV.
Open →Filter pasted CSV rows by a keyword in a selected column.
Open →Click a point in an image to sample its HEX and RGB color.
Open →Resize an image to the pixel dimensions you need.
Open →Reduce image file size by changing quality and maximum width.
Open →Crop an exact image area using coordinates and dimensions.
Open →Convert an image between PNG, JPEG, and WebP.
Open →Remove a selected color and export a transparent PNG.
Open →Edit HTML and preview the rendered browser result.
Open →Add line breaks and indentation to compressed HTML.
Open →Format one-line SQL into a more readable layout.
Open →Create a smaller copy of CSS, JavaScript, or HTML.
Open →Enter Markdown and check how it will render.
Open →Encode special HTML characters or restore entity references.
Open →Convert between image files and Base64 Data URLs.
Open →Inspect Unicode code points for text, symbols, and emoji.
Open →Convert between text and binary, decimal, or hexadecimal bytes.
Open →Type an expression and calculate it directly in your browser.
Open →Count down from a chosen duration in your browser.
Open →Measure elapsed time and lap times in your browser.
Open →Extract email addresses from long text and remove duplicates.
Open →Create a placeholder PNG with exact dimensions and colors.
Open →Create a QR code from a URL or text in your browser, export PNG/SVG, and verify it by re-scanning.
Open →Create a QR code with a centered logo or illustration, export PNG/SVG, and re-scan it in your browser.
Open →Create a styled QR code with custom dots, colors and gradients, export PNG/SVG, then verify it by re-scanning.
Open →Test a QR image at full size, reduced size, lower contrast and light blur before publishing or printing.
Open →Generate favicon.ico and PNG icons from 16 to 512 px from one image in your browser.
Open →Select pages from a PDF and save them as a new PDF. The file is processed in your browser.
Open →Remove selected pages from a PDF and save the remaining pages as a new PDF.
Open →Paste a YouTube transcript, remove timestamps and adjacent duplicates, and clean it into readable text.
Open →Merge multiple PDF files in the selected order and save them as one PDF.
Open →Compress PDF files in your browser. Safe optimization avoids rasterizing pages; optional raster compression is available when you need stronger reduction.
Open →Split a PDF into multiple files by a chosen number of pages.
Open →Reorder PDF pages by entering a new order such as 3,1,2,4-6.
Open →Rotate selected PDF pages by 90°, 180°, or 270° and save the result.
Open →Convert multiple images into a single PDF in the selected order.
Open →Render each PDF page as a PNG or JPEG image.
Open →Add page numbers to a PDF with position, start number, and font size controls.
Open →Add a text watermark to every PDF page with opacity, angle, and size controls.
Open →Place a signature or stamp image on selected PDF pages and save the PDF.
Open →Detect image objects used inside a PDF and export them as PNG files.
Open →Convert HEIC or HEIF images to JPEG or PNG in your browser.
Open →Convert AVIF images to PNG or JPEG.
Open →Render SVG to PNG or JPEG at a chosen width.
Open →Compress multiple images with chosen format, quality, and maximum width.
Open →Resize multiple images to the same dimensions or maximum long edge.
Open →Rotate an image in 90° steps and flip it horizontally or vertically.
Open →Inspect EXIF, camera, date, GPS, and other image metadata.
Open →Re-encode an image to remove EXIF, GPS, and other metadata.
Open →Add a text watermark to an image with position, opacity, and size controls.
Open →Apply a mosaic effect to a selected rectangular area of an image.
Open →Compare two JSON values and list added, removed, and changed paths.
Open →Validate JSON data against a JSON Schema (Draft-07 style) and show errors.
Open →Run common JSONPath expressions against JSON and inspect matched values.
Open →Convert between JSON and YAML and check syntax errors.
Open →Convert between CSV and JSON arrays, including quoted fields and line breaks.
Open →Build and validate 5-field cron expressions with presets, a human-readable explanation, dialect notes, and a preview of the next five run times.
Open →Estimate browser, operating system, and device type from a User-Agent string.
Open →Calculate normalized IPv4/IPv6 CIDR ranges, first/last addresses and total size.
Open →Convert an IPv4 or IPv6 start/end range into the smallest exact CIDR list.
Use →Check title and meta description character counts, UTF-8 bytes, and recommended ranges.
Open →Preview how a title, URL, and description may look in a search result.
Open →Reorder, delete, and rotate PDF pages in one workflow.
Open →Add text to selected PDF pages with position, color, and size controls.
Open →Inspect PDF title, author, dates, and other metadata, and create a copy with basic metadata cleared.
Open →Extract text from selected or all PDF pages and save it as TXT.
Open →List every PDF page size in points, millimeters, and inches.
Open →Resize all PDF pages to A-series, Letter, or custom sizes with content fitting options.
Open →Crop PDF page boxes by specified top, bottom, left, and right margins.
Open →Rasterize PDF pages and rebuild them as a grayscale PDF.
Open →Convert PNG, JPEG, or WebP images to AVIF with adjustable quality.
Open →Extract animated GIF frames as individual PNG images.
Open →Convert multiple images to JPEG, PNG, WebP, or AVIF and optionally download a ZIP.
Open →Overlay two images and compare before/after with an interactive slider.
Open →Extract frequent colors from an image and show HEX codes and approximate shares.
Open →Calculate an image’s dominant color and average color as HEX values.
Open →Convert an image to grayscale and save it as PNG, JPEG, or WebP.
Open →Crop an image to rounded corners or a circle and save a transparent PNG.
Open →Crop images to common Instagram, Story, X, OGP, YouTube, and LinkedIn sizes.
Open →Validate SVG syntax and reduce size by removing comments and unnecessary whitespace.
Open →Extract icon images from an ICO file as PNG files by size.
Open →Create a favicon.ico containing multiple PNG-compressed sizes from 16 to 256 px.
Open →Create a vCard QR code from name, organization, phone, email, and URL fields.
Open →Generate basic title, description, robots, and viewport tags.
Open →Preview a social Open Graph card from title, description, URL, and image URL.
Open →Generate Open Graph tags including title, description, URL, image, and card type.
Open →Generate a canonical link tag from an absolute canonical URL.
Open →Generate hreflang and x-default tags from language-code and URL pairs.
Open →Build a robots.txt file from user-agent, allow, disallow, and sitemap settings.
Open →Generate an XML sitemap from URLs with optional lastmod, changefreq, and priority.
Open →Format or minify JSON-LD and check basic @context and @type structure.
Open →Create a Wi-Fi connection QR code from SSID, security type, and password.
Open →Combine multiple images into a grid with adjustable columns, gaps, and background.
Open →Visualize pixel differences between two images as a heatmap.
Open →Apply sepia and hue adjustments to an image and export the result.
Open →Adjust brightness, contrast, and saturation and export the result.
Open →Apply blur or lightweight sharpening to an image and export it.
Open →Create printable multi-up ID photo layouts for common paper and photo sizes.
Open →Create a labeled thumbnail contact sheet from multiple images.
Open →Pack multiple images into a regular PNG sprite sheet.
Open →Generate a QR code that opens a prefilled email draft.
Open →Generate a QR code for dialing a phone number.
Open →Generate a QR code for an SMS recipient and message.
Open →Generate a QR code from latitude and longitude coordinates.
Open →Generate a QR code containing a calendar event.
Open →Read the content of a QR code image in your browser.
Open →Generate Code128, EAN-13, UPC-A and other barcodes in your browser.
Open →Detect and read supported barcodes from an image using browser APIs.
Open →Generate Twitter/X Card meta tags from page information.
Open →Check common directives and basic syntax in a pasted robots.txt file.
Open →Check XML syntax and basic URL entry structure in an XML sitemap.
Open →Generate FAQPage JSON-LD from question-and-answer pairs.
Open →Generate BreadcrumbList JSON-LD from labels and URLs.
Open →Preview recommended Open Graph image ratios and safe areas.
Open →Generate favicon, apple-touch-icon, and manifest link tags.
Open →Generate a PWA manifest.webmanifest file from form fields.
Open →Validate required and recommended fields in a Web App Manifest JSON.
Open →Build and parse URL query strings from key-value pairs.
Open →Look up common MIME types by extension or MIME value.
Open →Look up HTTP status code meanings and categories.
Open →Convert internationalized domain names between Unicode and Punycode.
Open →Generate Data URIs from text/files and parse Data URIs.
Open →Count words, sentences, paragraphs, characters, and estimated reading time in real time.
Open →Convert ASCII letters, numbers, symbols, and spaces between full-width and half-width forms.
Open →Normalize text as NFC, NFD, NFKC, or NFKD and inspect differences and code points.
Open →Clean repeated spaces, trailing whitespace, blank lines, and newlines for common text workflows.
Open →Convert text line endings among LF, CRLF, and CR and download the result.
Open →Extract URLs, hostnames, or origins from text and logs, then deduplicate and sort the results.
Use →Strip HTML tags into plain text and optionally normalize whitespace and line breaks.
Open →Convert Markdown to HTML in the browser with source output and a safe preview.
Open →Mask emails, phone numbers, IP addresses, and card-number-like patterns locally in the browser.
Open →Detect enclosed numbers, Roman numerals, unit symbols, emoji, and other characters that may have compatibility concerns.
Open →Edit CSV in a browser table with type-aware sorting, row and column controls, Undo, leading-zero preservation, and UTF-8 / Shift_JIS input.
Open →Clean whitespace, blank rows, duplicates, and null markers, then remove, reorder, or rename columns with preview. Supports UTF-8 / Shift_JIS input.
Open →Compare two CSV files by headers, rows, and cells and inspect additions, removals, and changes.
Open →Reorder CSV columns, omit unwanted columns, and optionally keep unspecified columns at the end.
Open →Bulk-replace values in selected or all CSV columns using literal text or regular expressions.
Open →Convert CSV to a Markdown table with alignment options and escaped pipe characters.
Open →Parse a Markdown table into CSV and download the result.
Open →Join two CSV datasets by key using INNER, LEFT, or FULL join and export the result.
Open →Calculate weekday, day of year, and nearby dates with the same weekday.
Open →Calculate ISO week number, ISO week-year, and the week start/end dates.
Open →Convert date/time values between IANA time zones and inspect UTC, offset, and localized output.
Open →Convert a date/time value to ISO 8601, RFC 3339, Unix seconds/milliseconds, and localized forms.
Open →Create a downloadable ICS calendar event from title, dates, location, and description.
Open →Calculate future value and principal/interest breakdown from rate, term, contributions, and compounding frequency.
Open →Calculate monthly loan payment, total interest, and an amortization schedule.
Open →Calculate ROI, net profit, and break-even return from investment cost and return.
Open →Calculate compound annual growth rate from starting value, ending value, and years.
Open →Estimate LTV, LTV/CAC ratio, and CAC payback from ARPU, gross margin, churn, and CAC.
Open →Calculate ROAS, CPA, CPC, CTR, and conversion rate from spend, revenue, clicks, impressions, and conversions.
Open →Convert length, mass, temperature, area, volume, speed, and data units.
Open →Generate a 9-step tint/shade palette from one color and copy CSS variables.
Open →Generate complementary, analogous, triadic, and tetradic harmonies from a base color.
Open →Check foreground/background contrast ratio against WCAG AA and AAA thresholds.
Open →Build linear, radial, or conic gradients with live preview and copy-ready CSS.
Open →Tune offset, blur, spread, color, and inset to generate box-shadow CSS.
Open →Preview and generate CSS text-shadow values.
Open →Adjust four corner radii together or separately and generate CSS.
Open →Generate glassmorphism CSS by tuning transparency, blur, border, and radius.
Open →Mix two colors at a chosen ratio and get HEX/RGB output.
Open →Convert between #RRGGBBAA and RGBA alpha color formats.
Open →Preview brightness, contrast, saturation, blur and more to generate CSS filter.
Open →Combine translate, rotate, scale and skew with live CSS transform preview.
Open →Calculate SHA-1, SHA-256, SHA-384, or SHA-512 hashes locally for a file.
Open →Hash a file locally and compare it with an expected checksum.
Open →Preview batch renames with prefix, suffix, numbering, and search/replace.
Open →Sanitize filenames by removing problematic characters and trailing dots/spaces.
Open →Calculate total, average, largest, and smallest sizes for selected files.
Open →Export selected file names, sizes, types, and modified dates as CSV or JSON.
Open →Detect byte-identical duplicate files by grouping SHA-256 hashes.
Open →Inspect common magic bytes and compare detected type with extension and MIME.
Open →Generate a list of dates from a start, end, and interval.
Open →Generate recurring dates by day, week, month, or year from a start date.
Open →Calculate a deadline after a number of calendar days or weekdays.
Open →Find meeting times that fall inside working hours for multiple UTC offsets.
Open →Estimate time to reach a savings goal from current balance, monthly saving, and return.
Open →Calculate break-even units and revenue from fixed cost, price, and variable cost.
Open →Calculate tip, total bill, and per-person amount for a group.
Open →Calculate absolute change, percentage change, and multiple between old and new prices.
Open →Validate ISBN-10 and ISBN-13 length and check digits.
Open →Convert 978-based ISBNs between ISBN-10 and ISBN-13 and recalculate check digits.
Open →Flatten nested JSON into dot-separated key paths.
Open →Rebuild nested JSON from dot-separated flat keys.
Open →Infer TypeScript interfaces/types from a JSON sample.
Open →Resolve values in JSON with RFC 6901 JSON Pointer.
Open →Convert CSV rows and columns into XML in the browser.
Open →Convert repeated XML elements into tabular CSV.
Open →Convert XML to JSON while preserving attributes and text.
Open →Convert JSON into XML with a custom root element.
Open →Encode or decode URI components in the browser.
Open →Generate 1–1000 UUID v4 or v7 values with selectable output formatting.
Open →Generate random strings with configurable length, count, and character sets.
Open →Decode JWT exp, nbf, and iat claims and inspect time validity.
Open →Build a Content-Security-Policy header from common directives.
Open →Build a Permissions-Policy header for browser features.
Open →Build Cache-Control directives including max-age and immutable.
Open →Build example CORS response headers from origin and method settings.
Open →Choose and generate a Referrer-Policy header.
Open →Generate security.txt fields for RFC 9116 deployment.
Open →Generate Apache .htaccess 301/302 redirect rules.
Open →Generate nginx 301/302 redirect rules.
Open →Convert three-digit chmod values to rwx permission notation.
Open →Compare two Semantic Version 2.0.0 values.
Open →Resolve a relative URL against a base URL using browser URL rules.
Open →Generate sha256/384/512 Subresource Integrity hashes for text or files.
Open →Count word or character N-gram frequencies in text.
Open →Count word, character, or line frequencies and shares.
Open →Add line numbers to text or remove existing line-number prefixes.
Open →Transpose CSV rows and columns.
Open →Group CSV by a key column and calculate count, sum, average, min, or max.
Open →Validate ISSN format and check digit.
Open →Calculate stage and overall conversion rates from visitors, leads, and customers.
Use →Calculate customer churn rate from starting customers and customers lost.
Use →Calculate customer retention from starting, ending, and newly acquired customers.
Use →Calculate average order value from revenue and order count.
Use →Calculate average revenue per user from revenue and active users.
Use →Estimate CAC payback months from acquisition cost, monthly ARPU, and gross margin.
Use →Count characters and words in ad copy against a custom length limit.
Use →Check post length plus URL, hashtag, and mention counts.
Use →Estimate how many months cash will last from current cash and monthly net burn.
Use →Calculate average monthly burn rate from beginning and ending cash balances.
Use →Calculate inventory turnover and days in inventory from COGS and average inventory.
Use →Calculate reorder point from daily demand, lead time, and safety stock.
Use →Estimate safety stock from maximum and average demand and lead times.
Use →Calculate economic order quantity from annual demand, order cost, and holding cost.
Use →Calculate annual straight-line depreciation from cost, salvage value, and useful life.
Use →Calculate commission and total compensation from sales, rate, and base pay.
Use →Convert annual salary into monthly, weekly, daily, and hourly equivalents.
Use →Calculate regular and overtime pay from hours, hourly rate, and overtime multiplier.
Use →Calculate revenue change and growth rate between two periods.
Use →Calculate break-even revenue from fixed costs and contribution margin ratio.
Use →Parse raw HTTP headers into names and values and flag duplicate fields.
Use →Parse a Cookie header into key-value pairs with optional URL decoding.
Use →Parse KEY=VALUE dotenv text, validate variable names, and convert it to JSON.
Use →Build Basic or Bearer Authorization headers locally in your browser.
Use →Escape plain text so it can be safely used as a regex literal.
Use →Build a SQL IN (...) list from one value per line.
Use →Sort lines naturally so file2 comes before file10.
Use →Split a line-based list into groups of a chosen size.
Use →Wrap text near a chosen character width for easier copying and reuse.
Use →Align delimited text into padded columns for monospaced display.
Use →Calculate CSS selector specificity as ID, class/attribute/pseudo-class, and element components.
Use →Convert px, rem, em, vw, and vh using configurable font and viewport dimensions.
Use →Convert dates between HTTP Date (RFC 7231), ISO 8601, and Unix seconds.
Use →Validate and normalize IPv4/IPv6 addresses and identify common special-purpose ranges.
Use →Validate a MAC address and format it with colons, hyphens, or Cisco-style dots.
Use →Validate UUID format, version and variant, and inspect the embedded time in v7.
Use →Generate sortable 26-character ULIDs locally in your browser.
Use →Convert a common curl command into browser fetch() code.
Use →Build a reusable curl command from URL, HTTP method, headers, and request body.
Use →Parse an Accept-Language header into language tags and q-values sorted by preference.
Use →Sort CSV rows by a selected column as text or numbers in ascending or descending order.
Use →Extract distinct values and occurrence counts from a selected CSV column.
Use →Count blank, NULL, NA, and other common missing-value markers by CSV column.
Use →Calculate count, sum, mean, median, min, max, and standard deviation for a numeric CSV column.
Use →Create a simple SUM or COUNT pivot table from row, column, and value fields.
Use →Infer integer, number, boolean, date, or string types for each CSV column and show blank rates.
Use →Randomly sample rows without replacement from CSV, with an optional deterministic seed.
Use →Generate SQL INSERT statements from CSV headers and rows.
Use →Combine two line-based lists into a deduplicated union.
Use →Extract items that appear in exactly one of two line-based lists.
Use →Generate every pairwise combination (Cartesian product) from two line-based lists with a configurable separator.
Use →Indent or dedent multiline text using spaces or tabs.
Use →Calculate ending MRR from starting MRR, new, expansion, contraction, and churned MRR.
Use →Convert MRR to ARR and optionally calculate annual recurring-revenue growth.
Use →Calculate net revenue retention from starting MRR, expansion, contraction, and churned MRR.
Use →Calculate open rate, CTR, CTOR, and unsubscribe rate from email-campaign counts.
Use →Compare A/B conversion rates, absolute difference, relative uplift, and an approximate two-proportion z-test.
Use →Calculate ideal spend, pacing ratio, and required daily spend from campaign budget and elapsed days.
Use →Check whether two date ranges overlap and calculate the overlapping dates and duration.
Use →Generate appointment time slots from start/end times, slot duration, and interval.
Use →Insert blank pages at specified positions in a PDF and choose the blank-page size.
Open →Interleave two PDFs page by page, such as A1, B1, A2, B2.
Open →Place multiple PDF pages on each output sheet in 2-up, 4-up, 6-up, or 9-up layouts.
Open →Flatten PDF form fields into fixed page content for easier sharing and archiving.
Open →List PDF form field names, types, values, and required/read-only states.
Open →Extract URL link annotations from a PDF with page numbers and export them as CSV.
Open →Add padding and borders around an image and export as PNG, JPEG, or WebP.
Open →Replace pixels near a chosen source color with another color to change a simple background.
Open →Inspect transparent, semi-transparent, and opaque pixel ratios and the visible-content bounds.
Open →Preview an image with approximate protanopia, deuteranopia, tritanopia, or achromatopsia simulation.
Open →Reduce color levels to create a posterized image effect.
Open →Convert an image to black and white using a configurable threshold, with optional inversion.
Open →Analyze RGB and luminance histograms plus basic pixel statistics in the browser.
Open →Split an image into separate red, green, blue, and alpha channel images.
Open →Validate and format YAML, with an optional JSON preview.
Open →Convert between INI configuration text and JSON while preserving sections and key/value pairs.
Open →Apply an RFC 7396 JSON Merge Patch to a target JSON document.
Open →Sort a JSON array by a selected key path in ascending or descending order.
Open →Parse a Content-Type header into media type, charset, boundary, and other parameters.
Open →Parse an HTTP Accept header into media ranges and q-values sorted by preference.
Open →Parse a Content-Disposition header into disposition, name, filename, and filename* parameters.
Open →Sort URL query parameters by key/value and optionally remove common tracking parameters.
Open →Extract an HTML table and convert it to CSV.
Open →Rename CSV headers in bulk using a mapping or a replacement header list.
Open →Remove duplicate CSV rows by selected key columns, keeping the first or last occurrence.
Open →Split a CSV into separate files for each distinct value in a selected column.
Open →Normalize CSV headers to snake_case, camelCase, kebab-case, or safe identifier forms.
Open →Detect outliers in a numeric CSV column using IQR or z-score and extract flagged rows.
Open →Calculate requested percentiles such as P25, median, P90, and P95 from a numeric CSV column.
Open →Detect and remove CSV columns that are blank across all data rows.
Open →Export a selected folder structure as text, Markdown, or JSON.
Open →Compare two folders by relative path, size, and modified time and export differences.
Open →Summarize file counts and total size by extension in a selected folder.
Open →Analyze file-size buckets and list the largest files in a folder.
Open →Analyze last-modified dates, age buckets, oldest and newest files.
Open →Calculate required Mbps and MB/s from data size and target completion time.
Open →Plan chunked uploads from file size, chunk size, bandwidth, and parallelism.
Open →Generate a SHA checksum manifest for multiple files or a folder.
Open →Convert UTF-8 text to and from URL-safe Base64.
Open →Generate OAuth 2.0 PKCE code_verifier and S256 code_challenge locally.
Open →Normalize URLs, remove common tracking parameters, and sort query parameters.
Open →Convert between newline-delimited JSON (NDJSON/JSONL) and JSON arrays.
Open →Compare query parameters between two URLs and identify additions, removals, and changes.
Open →Estimate HTTP cache freshness remaining from Date, Age, and max-age.
Open →Generate batches of SQL INSERT statements from simple column type definitions.
Open →Compare matching PDF pages and render a pixel-difference heatmap with metrics.
Open →Convert a selected Excel sheet to CSV, or UTF-8 / Shift_JIS CSV to Excel, with preview, delimiter and BOM options, and leading-zero preservation.
Open →Normalize a CSV date column to YYYY-MM-DD and report rows that could not be converted.
Open →Check uniqueness of a CSV key column and list duplicate keys with row numbers.
Open →Calculate two numeric CSV columns and append the result as a new column.
Open →Extract the top N rows by a numeric value within each CSV group.
Open →Fill missing CSV values using a constant, mean, median, or forward fill.
Open →Analyze line lengths and identify lines exceeding a chosen character threshold.
Open →Count ASCII, Hiragana, Katakana, Han, emoji, whitespace, and other characters.
Open →Convert lists among comma, tab, semicolon, pipe, and newline delimiters.
Open →Extract, normalize, basically validate, and deduplicate a list of email addresses.
Open →Calculate days inventory on hand and inventory turns from average inventory and COGS.
Open →Calculate the cash conversion cycle from DIO, DSO, and DPO.
Open →Generate front/back saddle-stitch booklet page order for a multiple-of-four page count.
Open →Normalize DOI strings or doi.org URLs and generate standard and Markdown links.
Open →No matches. Try a shorter term or another expression.
Decisions, failure modes and workflows around the tools.
Separate AI crawler configuration into access directives, guidance metadata, and indexing directives so each file or header is used for the right job.
Email authentication and certificate issuance controls all use DNS, but they solve different problems. This guide separates their roles and setup order.
Separate CSV failures into encoding, delimiter and quoting problems instead of treating them as one issue.
Treat merge, page organization and compression as separate steps. Keep originals, decide order first, fix pages next, and compress only when the delivery requirement actually needs it.
Newer is not automatically better. Choose based on photos vs graphics, transparency, editing compatibility and the actual delivery target.
QR error correction provides margin, not unlimited cover. Treat quiet zone, contrast, logo area and final-device testing as one checklist.
A Mon–Fri calendar is not enough for Japan. National holidays, substitute holidays, citizens’ holidays and company shutdowns matter, and start-day counting can move a deadline by one day.
These controls look related but solve different problems: crawling, indexing, canonical selection and URL discovery.