Date Format Normalizer
Choose a source and output pattern, then normalize a date locally.
Choose both formats explicitly. Ambiguous dates are never guessed.
Normalized date
A QUICK WALKTHROUGH
How to use this tool
- Enter a date using the selected source pattern.
- Choose the output pattern.
- Normalize and review the result.
Explicit formats only
Supported patterns are YYYY-MM-DD, DD/MM/YYYY, MM/DD/YYYY, and YYYY/MM/DD. The selected source format controls interpretation; the tool never guesses ambiguous dates.
Calendar validation
Impossible dates such as 31/02/2026 are rejected before formatting.
Local processing
Parsing and formatting happen in this browser. No date is uploaded or stored.
GOOD TO KNOW
Common questions
Why must I choose a source format?
Numeric dates such as 03/04/2026 can mean different calendar dates. An explicit selection avoids guessing.
Does it support times?
No. This tool handles the four date-only patterns shown in the controls.
Are invalid dates accepted?
No. Calendar validity is checked before output.