Convert dates between formats in a CSV: ISO 8601, US (MM/DD/YYYY), EU (DD/MM/YYYY), and Unix timestamps.
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Dates are where imports break. This converts one column between ISO (YYYY-MM-DD), US (MM/DD/YYYY), EU (DD/MM/YYYY), dotted and dashed variants, and Unix timestamps taken at UTC midnight.
The hard part is knowing whether 03/04/2024 means 3 April or 4 March. The tool reads the column for evidence, and a single value with a first component above 12 settles the whole column as day-first. When a column is genuinely ambiguous, or mixes both conventions, it stops and asks you to name the source format rather than guessing. A European bank statement heading into a system that expects ISO is exactly this situation.
Values that cannot be parsed are left as they are and listed by row number, so a stray "pending" in a date column gets reported instead of silently converted. A five-row before-and-after preview sits above the result table.