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Unix timestamp

Time

Convert between epoch seconds/ms and ISO dates.

What this tool helps with

Unix time counts seconds since 1970-01-01 UTC, ignoring leap seconds. APIs, logs, and JWT exp/iat claims use it because it is timezone-free and trivially comparable. The common trap is the unit: many systems use milliseconds, not seconds, so a value off by a factor of 1000 lands in 1970 or the year 50000. This converter goes both directions between epoch seconds/ms and ISO 8601, in the browser, with no network call.

1779746228 · 2026-05-25T21:57:08.612Z

Local time:

How to use Unix timestamp

  1. Open the Unix timestamp page and paste, type, or generate the unix input you want to work with.
  2. Pick the options you need so the tool can convert between epoch seconds/ms and ISO dates
  3. Copy the epoch result with one click and use it in your next step — terminal, editor, ticket, or anywhere else you need it.

Common uses

  • Reach for Unix timestamp when you need to convert between epoch seconds/ms and ISO dates during debugging, code review, or content preparation.
  • Skip installing a desktop unix app — open this time utility on a shared machine, an iPad, or a colleague's laptop and it just works.
  • Bookmark or share the page when you and your team keep coming back to the same unix, epoch, timestamp, and date workflow.

FAQ

Seconds or milliseconds — how do I tell?

A current epoch in seconds is 10 digits; in milliseconds it is 13. JavaScript's Date.now() and most JS APIs use milliseconds; most Unix tooling and JWTs use seconds.

What timezone is a Unix timestamp in?

None — it is an absolute instant in UTC. Timezone only matters when you format it into a human date, which is a display concern, not a property of the timestamp.

What is the year-2038 problem?

Systems storing Unix time in a signed 32-bit integer overflow in January 2038. Anything using 64-bit time (which is now standard) is unaffected.

Related tools

Wrangle epochs and timestamps.