Dates
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About Dates
Standardize messy dates into ISO-8601 format.
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.
Category: Cleaning & PreparationCommon Use Cases
- Standardizing dates from a CSV that mixes MM/DD/YYYY and DD/MM/YYYY entries from different regions
- Converting Excel serial date numbers back into readable, sortable dates
- Preparing a date column for import into a database that requires ISO-8601 format
Key Features
- Parses common regional date formats automatically
- Converts Excel serial date numbers to calendar dates
- Standardizes output to ISO-8601 (YYYY-MM-DD)
- Flags rows where a date couldn't be confidently parsed
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.
Frequently Asked Questions
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.
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.
Read the related guide →