Date Format Converter
About Date Format Converter
Paste a date or Unix timestamp and see it in the common formats people need: ISO 8601, US, EU, Unix seconds, Unix milliseconds, UTC and spoken date/time.
Dates are easy to misread when formats cross borders. 03/04/2026 can mean March 4 or 3 April depending on the system. This converter includes an ambiguity switch for numeric dates so you can choose the intended order.
For exact instants, use ISO 8601 or Unix timestamps. For human-facing copy, use the spoken output.
How the input is read
A 10-digit number is read as Unix seconds and a 13-digit number as milliseconds, so 1700000000 is 14 November 2023 at 22:13:20 UTC. Numeric dates may use slashes, dots or hyphens. When the year comes first (2026-03-04) the order is year, month, day; otherwise the order depends on the ambiguity setting. A two-digit year is read as 20xx, so 4/3/26 means 2026.
Dates that do not exist, such as 31/02/2026, are rejected rather than rolled into March. Anything the numeric rules do not recognise, like 4 March 2026 or Mar 4, 2026 10:30, is handed to the browser's own date parser.
The 03/04/2026 problem
A numeric date with both numbers 12 or under is genuinely ambiguous: 03/04/2026 is 4 March in the US and 3 April almost everywhere else. Auto assumes US order unless the first number is above 12, in which case it must be day first — 25/12/2026 can only be 25 December. If your source is not American, set the order to DD/MM explicitly instead of trusting Auto, and check the Spoken row, which spells the month out.
Which output to copy
ISO carries your local offset, such as 2026-03-04T00:00:00+05:30, so it reads as the date you typed; the UTC row shows the same instant in Greenwich time. Use ISO for an API field or a database, Unix seconds for logs and many programming languages, Unix milliseconds for JavaScript's Date, and Spoken when you need wording for a document. All of them describe the same moment.
Because the offset comes from your device, the same input gives different ISO and UTC rows for someone in another time zone. If an instant must be unambiguous across people, share the UTC or Unix value rather than a local date.
What you can use it for
- Turn a Unix timestamp into a readable date
- Convert a date into ISO format for an API
- Check US versus EU date ordering
- Copy UTC or spoken date output for documentation
How it works, step by step
- 1
Paste a date
Use ISO, slash dates, text dates or a Unix timestamp.
- 2
Set ambiguous order
Choose MM/DD or DD/MM when needed.
- 3
Read formats
The converted formats update immediately.
- 4
Copy output
Copy the exact format you need.
Frequently asked questions
How does it handle 03/04/2026?
Use the ambiguous-order dropdown. Auto assumes US order unless the first number is greater than 12, in which case it treats it as day/month/year.
Can I paste a Unix timestamp?
Yes. A 10-digit value is treated as seconds and a 13-digit value as milliseconds.