Headers become JSON keys
With headers enabled, name,score and Alice,95 become an object such as {"name":"Alice","score":"95"}. CSV does not carry numeric type information, so values start as strings.
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Convert between CSV and JSON arrays, including quoted fields and line breaks.
Move between a CSV table and a JSON array for API tests, scripts, or spreadsheet review. CSV→JSON can use the first row as object keys; JSON→CSV expands flat object keys into columns.
With headers enabled, name,score and Alice,95 become an object such as {"name":"Alice","score":"95"}. CSV does not carry numeric type information, so values start as strings.
CSV can contain the same header twice, but a JSON object cannot preserve two values under the same key. The converter therefore blocks blank or duplicate headers in object mode instead of silently overwriting a column.
If the first row is data too, disable headers and the CSV shape is preserved as nested arrays rather than objects.
Object arrays are expanded using the union of their keys; missing keys become blank cells. Deeply nested objects and arrays are not automatically flattened into a relational CSV schema.
Turn a small fixture CSV into JSON for a script, or export a flat API response to CSV for human review. Check header uniqueness and nesting before conversion.