# Free Unix Timestamp Converter Online | Alher Tech

> Free online Unix timestamp converter. Convert epoch seconds or milliseconds to ISO date strings and local time. Live clock, copy-friendly output.

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Convert Unix timestamps to human-readable dates and back. Supports seconds, milliseconds, and multiple timezones.

Free online Unix timestamp converter. Convert epoch seconds or milliseconds to ISO date strings and local time. Live clock, copy-friendly output.

## Frequently asked questions

### What is a Unix timestamp?

A Unix timestamp is the number of seconds that have elapsed since January 1st, 1970 UTC (the Unix epoch). It's a language- and timezone-agnostic way to represent a moment in time.

### Seconds or milliseconds, which do I use?

Classic Unix systems, databases like Postgres, and many APIs use seconds. JavaScript's Date.now(), Java, and most modern APIs use milliseconds. If your number has 10 digits it's seconds; 13 digits means milliseconds.

### What happens in 2038?

The 32-bit signed Unix timestamp overflows on 19 January 2038 at 03:14:07 UTC. Most modern systems now use 64-bit timestamps, which don't overflow for the next ~292 billion years.

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