Unix Timestamp Converter for Developers

Convert epoch seconds or milliseconds to a human date and back, with timezone awareness.

Tools for engineers who would rather not context-switch into yet another tab to validate a JWT or generate a UUID. Everything runs in your browser, your payloads never leave the machine, and the pages load fast enough that you can leave them open in a sidebar while you debug.

Open the Unix Timestamp Converter →

What it does for Web and API developers

How to use it

  1. Paste an epoch number or a date string into the field; the other updates as you type.
  2. If you are debugging a "this should not have expired yet" ticket, switch the rendered timezone until the math lines up with what the server logs say.
  3. Copy the epoch or the ISO string into your code, your SQL query, or your bug report.

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Common questions

Is my timestamp in seconds or milliseconds?

Count the digits: ten digits is seconds, thirteen is milliseconds. The failure mode is quiet rather than loud - a millisecond value read as seconds lands decades away from the date you expected, and a seconds value read as milliseconds collapses towards January 1970.

Why is my converted time off by a whole number of hours?

The epoch itself is UTC; only the display is local. Store and transmit UTC and convert at the edges, and when a value comes from a system that stored a local time without a zone there is no correct conversion - only a decision about which zone was meant.

What happens to timestamps in 2038?

Any system holding the value in a signed 32-bit integer runs out of range in January 2038. Modern 64-bit platforms are fine, but the value can still be narrowed on the way through a database column or a language binding - worth checking before you build something with a long horizon.