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Normalize messy dates in yourCSV
Detect date columns automatically, parse mixed formats, and rewrite every cell to one clean standard — ISO, US, EU, or Unix.
Detect date columns automatically, parse mixed formats, and rewrite every cell to one clean standard — ISO, US, EU, or Unix.
Upload a CSV, pick the date columns (or let the tool find them), choose an output format, and download a file where every date follows one consistent pattern.
Drop in any file with date columns. Parsing happens in your browser, so nothing is uploaded to a server.
Select the date columns to convert — or leave the picker empty to auto-detect them — then pick ISO 8601, US, EU, or Unix output.
Every parseable date is rewritten to your chosen format; values that aren't dates are left exactly as they were. Export the cleaned CSV.
Mixed date formats break sorting, joins, and downstream tools. One consistent standard makes every later step reliable.
ISO 8601 dates sort correctly as plain text, so chronological order survives spreadsheets and scripts that treat columns as strings.
When two files agree on date format, keys line up and rows match instead of silently dropping out of joins.
Databases, BI tools, and pipelines expect predictable formats. Normalizing up front avoids import errors and ambiguous M/D/Y guesses.
All parsing and reformatting run client-side. Sensitive timestamps and records never leave your browser.