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Free tool

Unix Timestamp Converter

Convert epoch seconds or milliseconds to readable dates in UTC or any time zone, and dates back to timestamps, with a live clock.

Runs entirely in your browser. Nothing you enter is sent to a server.

Current time

Epoch seconds
Epoch milliseconds
ISO 8601 (UTC)

Convert

Result

Enter a timestamp or date to see the conversions.

How it works

A Unix timestamp counts seconds since 1 January 1970 00:00:00 UTC. Multiply by 1,000 for milliseconds. This tool turns a number into a JavaScript date, then formats that single instant as an ISO 8601 string, as a UTC string and in the time zone you choose using your browser’s built-in Intl support, so daylight saving rules are handled for you.

To go the other way, type an ISO 8601 date (for example 2026-03-01T12:00:00Z) or pick a date and time from the picker, which is read in your device’s local time zone. The relative time (“3 hours ago”, “in 2 days”) is measured against your device clock.

Common uses

  • Reading timestamps in logs, database rows, JWT claims and API responses.
  • Checking when a cache entry, certificate or session expires.
  • Building test data and cron-style schedules with exact epoch values.
  • Comparing the same moment across the time zones of a distributed team.

Frequently asked questions

What is a Unix timestamp?

It is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970 (the Unix epoch), not counting leap seconds. Because it is a single number with no time zone, it is a convenient way for systems to store and compare moments in time.

How can I tell whether a timestamp is in seconds or milliseconds?

Current timestamps in seconds have 10 digits and in milliseconds 13 digits. JavaScript’s Date.now() returns milliseconds, while most Unix tools and many APIs use seconds. With the unit set to auto-detect, this tool treats values of 100 billion or more as milliseconds, and you can force either unit.

Why does the local time differ from UTC?

A timestamp identifies one instant. UTC and each time zone are just different ways of writing it as a calendar date and clock time. Pick a time zone to see the same instant there, including daylight saving time rules supplied by your browser.

What is the Year 2038 problem?

Systems that store the timestamp as a signed 32-bit integer overflow after 03:14:07 UTC on 19 January 2038 (2,147,483,647 seconds). Modern systems use 64-bit values, which this tool handles through JavaScript dates within the range browsers support.

Which date formats can I paste in?

ISO 8601 strings such as 2026-03-01T12:00:00Z or 2026-03-01 are the most reliable. Other formats that your browser’s Date.parse understands also work, but their interpretation can vary between browsers, so prefer ISO 8601.

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