Standardize messy date formats in a CSV.
Mixing 03/14/2024 with 14 Mar 2024 and 2024-03-14 in the same column? CSVTidy detects the date column, parses each row, and rewrites the whole column in the format you pick — ISO, US, or EU.
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Drop a CSV or Excel file here
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Common questions
Which date formats can it parse?
ISO (2024-03-14), slash formats (03/14/2024, 14/03/2024, 03-14-2024), month-name formats (14 Mar 2024, March 14, 2024, 14-Mar-24), and two-digit years (with 1970–2069 auto-windowing).
How does it handle ambiguous formats like 01/02/2024?
The parser defaults to auto-detection: if one interpretation is invalid it picks the other; otherwise it prefers MDY (US-heavy input). You can force MDY, DMY, or YMD manually in the full cleaner.
Do you support Excel serial dates?
When you upload an .xlsx file, Excel serial dates are typically converted to text by the sheet's own formatting on export. The upcoming Pro version adds explicit Excel-serial parsing.