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Dates

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Supported formats: .csv,.xlsx,.xls,.xlsm,.xlsb,.tsv

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AboutDates

Standardize messy dates into ISO-8601 format.Category: Cleaning & Preparation
Standardizing dates from a CSV that mixes MM/DD/YYYY and DD/MM/YYYY entries from different regionsConverting Excel serial date numbers back into readable, sortable datesPreparing a date column for import into a database that requires ISO-8601 format
The Dates tool is compatible with:.Run Date Reformatter before Date Decomposition if you need separate year, month, and day columns afterward, or before Column Validator to confirm every row now matches a consistent date type.
Date Reformatter parses the inconsistent date formats common in real-world exports, MM/DD/YYYY, DD-MM-YY, "March 3rd, 2024," Excel serial numbers, and more, and standardizes them all into ISO-8601 (YYYY-MM-DD). This removes the US/EU date-order ambiguity that causes silent misreads in databases, APIs, and spreadsheet formulas.

Frequently Asked Questions:

What date formats can it parse?

It's built to handle the messy, inconsistent date formats common in real-world exports (MM/DD/YYYY, DD-MM-YY, text dates, etc.) and standardize them.

Why ISO-8601 specifically?

ISO-8601 (YYYY-MM-DD) is the format databases, APIs, and most software expect, which avoids the US/EU date-order ambiguity.


Built for analysts and developers who've been burned by a date column that silently swapped day and month between systems.