Regex for a YYYY-MM-DD Date
Regex to match dates in YYYY-MM-DD format, restricting months to 01–12 and days to 01–31. Test it against valid and invalid dates.
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Regex for a YYYY-MM-DD Date
This pattern checks the shape of an ISO date and keeps the month between 01 and 12 and the day between 01 and 31. It does not know that February 30 is impossible, so check real validity in code.
Worked example: Valid and invalid ISO dates
Pattern /^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$/ — test strings
^\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$
2026-01-31
1999-12-01
2026-13-01
2026-00-10
2026-1-5Result for each line
✓ match 2026-01-31 ✓ match 1999-12-01 ✗ no match 2026-13-01 ✗ no match 2026-00-10 ✗ no match 2026-1-5
Practical tip
Combine regex and parsing: use the regex for format, then check new Date(str) round-trips to the same string to reject impossible dates like 2026-02-30.
How to use this Regex Tester
- 1Use the live tool above — it runs entirely in your browser and never uploads your data.
- 2Paste the sample from the worked example, or use your own input.
- 3Copy the result, then adapt the same steps in your editor, script, or pipeline.
Regex for a YYYY-MM-DD Date FAQs
Does this regex reject February 30?
No. It accepts any day 01–31 in any month. Reject impossible calendar dates with a date library after the format check.
How do I allow slashes or dots as separators?
Replace the dash with a character class: [-/.]. Add a backreference if you want the same separator used twice.
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