What happens to invalid date entries?

You can choose how to handle invalid or unparseable dates: leave them blank, keep the original text, or flag them for review.

Is there a limit to the file size?

Because processing happens locally, file size limits depend on your computer's memory, but typically files up to 100MB process quickly and smoothly.

Detect and standardize inconsistent date formats across CSV columns automatically. The safest way to process sensitive data w

Your files never leave your device. Processed locally. 100% private.

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Complete your task perfectly in just three straightforward steps.

Select the CSV file containing messy or inconsistent date formats.

Select the column containing the dates and specify your desired output format (e.g., YYYY-MM-DD).

Review the repaired dates and download your perfectly standardized CSV.

Everything you need to know about the Date Fixer.

What date formats does the tool support?

The tool can automatically detect and standardize a wide variety of formats, including DD/MM/YYYY, MM/DD/YYYY, UNIX timestamps, and ISO 8601 strings.

Is my CSV data kept private?

Yes! All date parsing and formatting is performed entirely in your web browser. Your data is never uploaded to any server.

Can I fix dates in multiple columns simultaneously?

Yes, you can select multiple columns and apply standardized formatting rules to all of them at once.

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