📅Date Format Batch Converter

Convert a mixed list of YYYYMMDD, MM/DD/YYYY, and other date formats at once

How to Use the Date Format Batch Converter

The Date Format Batch Converter takes a list of dates in inconsistent formats — one per line — and standardizes them all to a single format you choose. It automatically recognizes YYYYMMDD (8 digits), YYYY-MM-DD, YYYY/MM/DD, YYYY.MM.DD, and MM/DD/YYYY, and the output can be set to YYYY-MM-DD, YYYY/MM/DD, YYYY.MM.DD, MM/DD/YYYY, or YYYYMMDD from the dropdown.

It's especially useful for cleaning up data exported from spreadsheets, logs collected from different systems, or form submissions where everyone typed dates differently. Any line with an impossible date, like February 30, or a format the tool can't recognize, is marked "(unrecognized)" in the result so you can spot exactly which lines need a closer look. Conversion happens instantly in your browser, and the dates you enter are never sent to a server.

Frequently Asked Questions

Which date formats does it recognize?

It automatically recognizes YYYYMMDD (8 digits), YYYY-MM-DD, YYYY/MM/DD, YYYY.MM.DD, and MM/DD/YYYY.

Can I convert many lines at once?

Yes. Enter one date per line and every line is converted to your chosen format at the same time.

How are unrecognized dates shown?

Any line with an unrecognized format or an impossible date (like February 30) is marked "(unrecognized)" in the result so you can spot it right away.