Date & time
ISO 8601 Date Converter
Validate an ISO 8601 date and convert it to standard date representations. Nothing you enter leaves your browser.
Your result will appear here.
What this tool does
About the ISO 8601 Date Converter
Validate an ISO 8601 date and convert it to standard date representations. It helps make date, duration, and timezone work explicit so that assumptions can be checked before the result is reused.
It helps make date, duration, and timezone work explicit so that assumptions can be checked before the result is reused.
How to use it
- Enter an ISO 8601 date in the input pane. Use the example button if you want to see the expected syntax.
- Review the input for the structure shown in the example. Then select “Convert date.”
- Inspect the result for warnings or structural differences, then copy it into the destination system.
Practical example
Start with a known input
Try this sample input: 2026-07-12T14:30:00-04:00 Select “Convert date” and compare the result with the source before using it elsewhere.
What to know about the result
- ISO 8601 dates are least ambiguous when they include a timezone offset or the UTC designator Z.
- Processing happens in this browser. Your entered text and selected files are not sent to FormatCalc for conversion.
Common questions
Using the ISO 8601 Date Converter
Is the ISO 8601 Date Converter free to use?
Yes. FormatCalc's ISO 8601 Date Converter is free to use with no account required.
Is my data private when I use the ISO 8601 Date Converter?
Yes. This tool processes your input locally in your browser. FormatCalc does not upload or store what you enter.
How do I use the ISO 8601 Date Converter?
Paste or type your input, select any available options, and choose Convert date. You can then copy the result.
What should I check before using the result?
ISO 8601 dates are least ambiguous when they include a timezone offset or the UTC designator Z. Processing happens in this browser. Your entered text and selected files are not sent to FormatCalc for conversion.