Date Format Converter
Unix timestamps, ISO 8601, and readable dates — paste one, get all of them.
By opening this website or using its tools, you agree to our Terms and Privacy Policy.
Only affects the rows labelled with a zone. Unix timestamps and the UTC row are the same everywhere by definition.
Paste a Unix timestamp, an ISO 8601 string, or a date in almost any written form.
Your file never leaves your browser during processing
How it works
To convert a Unix timestamp or an ISO 8601 date, paste it above — the format is detected automatically and the same moment is shown as epoch seconds, epoch milliseconds, ISO 8601 in UTC and in your chosen time zone, an HTTP date, and a readable long form.
A Unix timestamp counts seconds since 1 January 1970 UTC, which makes it compact and unambiguous but unreadable. Most of the work of debugging a log line, an API response, or a database column is just getting that number back into a form you can reason about — and then, often, back out again in a different one.
Detection is by shape. A ten-digit number is seconds, thirteen digits is milliseconds, and sixteen is microseconds, which is what Postgres and most browser tracing formats emit. Lengths in between are genuinely ambiguous, and rather than pick silently the tool states which unit it assumed and shows what the other reading would be. Getting this wrong puts you decades off, so it is worth two seconds of checking.
Two parsing traps are called out on screen because they catch people regularly. A bare `2026-08-20` is defined by the ECMAScript specification to mean midnight *UTC*, while `2026-08-20T14:30` with no offset means 14:30 *local* — the same string family, two different rules, and the reason a date-only value can appear to shift a day for anyone west of Greenwich. The tool says which rule it applied to what you pasted. Calendar files sidestep the trap by writing times in UTC with a trailing Z, which is how the .ics event generator stores every timed event.
The zone selector affects only the rows labelled with a zone. Unix timestamps and the UTC row are the same everywhere by definition, which is the entire reason to store timestamps that way. To see one moment on several local clocks side by side, compare it across time zones.
FAQ
How do I convert a Unix timestamp to a date?
Paste the number above. The unit is detected from its length and the equivalent date is shown in UTC, in your chosen time zone, and in several standard text formats.
Is my timestamp in seconds or milliseconds?
Ten digits is almost always seconds and thirteen is milliseconds — a millisecond timestamp for a date near today is roughly a thousand times larger. Where the length is ambiguous, this page shows both readings so you can pick the one that lands in a plausible year.
Why does a date-only value like 2026-08-20 show a different day for me?
Because the ECMAScript specification parses a bare date as midnight UTC, which is the previous evening anywhere west of Greenwich. Add a time and an offset if you need it read as local.
What is ISO 8601?
The international standard date format — 2026-08-20T14:30:00Z, where the trailing Z means UTC. It sorts correctly as text and is unambiguous across regions, unlike 08/20/2026.
Can I convert a date to a Unix timestamp?
Yes, it works in both directions. Paste any readable date or ISO string and the epoch seconds and milliseconds are among the outputs.