How to use
- Open a file and choose the date column.
- Check the detected order (DMY or MDY) and the flagged rows.
- Pick an output format and download.
Worked example
Audit column: 25/12/2026, 03/04/2026, 4 Mar 2026, 2026-03-04, 31/02/2026, soon. Because 25 can only be a day, the column is read day-first: output 2026-12-25, 2026-04-03, 2026-03-04, 2026-03-04. 31/02/2026 is flagged as no such date and “soon” as not recognized; both are kept as written.
Supported formats and limits
| Input | CSV, XLSX, Text list |
|---|---|
| Output | CSV, XLSX, Text |
| Engine | Multi-pattern parser with column-level day/month order inference |
Limitations
- Two-digit years are mapped to 1950 to 2049 by default (configurable).
- Times are kept as written: an offset such as +02:00 is not converted to another time zone.
Questions
How does the tool handle a date that could be day-first or month-first?
It looks at the whole column. A value such as 25/12/2026 can only be day-first, so 03/04/2026 is then read as 3 April. If no value settles it, dates are read with your fallback order (day-first by default) and flagged as ambiguous. You can also force day-first or month-first: 03/04/2026 becomes 2026-04-03 or 2026-03-04.
What happens to invalid or unrecognized dates?
They are flagged, for example 31/02/2026 as no such date, and kept as written by default. You can choose to blank them instead, and show only flagged values to review them.
Are time zones converted?
No. Dates and times are kept as wall-clock values, so 2026-03-04T23:30:00+02:00 stays on 4 March. Unix timestamps are read as UTC.
Guides
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