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CSV CHECK

Check Klaviyo Historical Event CSV Import Errors

Check Timestamp, Email, ID, and $event_id fields before importing historical events.

Check CSV

🔒 Analysis runs in your browser. The CSV file itself is not uploaded to BlueprintLab.

What this tool checks

Checks the 50 MB limit, Timestamp, Person//Email / Person//ID, email format, $event_id for duplicate timestamps, and numeric $value.

About this tool

Check Klaviyo Historical Event CSV Import Errors is a free web tool from BlueprintLab Tools. Check a Klaviyo Historical Event CSV before import. Find Timestamp, Person//Email, ID, and $event_id format errors directly in your browser.

Designed for small marketing and CRM tasks such as preflight checks before importing campaign or customer data.

No account is required. The tool is designed to complete the task directly in your browser with a short input → process → result flow.

How to use

  1. Choose the file you want to check.
  2. Select “Check CSV”.
  3. Review the detected issues and save the result if needed.

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