Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and back. Auto-detects seconds and milliseconds.

Auto-detects seconds & msUTC & local timeNo data stored
Unix Timestamp
Enter a timestamp in seconds or milliseconds
Human-Readable Date
Pick a date and time to convert to a timestamp

What is a Unix Timestamp Converter?

A Unix timestamp (also called Epoch time or POSIX time) is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970, not counting leap seconds. It provides a language- and timezone-independent way to represent a specific moment in time as a single integer. Unix timestamps are used ubiquitously in databases, APIs, log files, JWT tokens, and operating systems. A converter translates between this numeric representation and human-readable date-time strings in any timezone.

Common Use Cases

  • Convert a timestamp from a server log or database record to a readable date
  • Debug JWT token expiry by converting the exp or iat claims
  • Calculate the Unix timestamp for a future date to use as a deadline or TTL
  • Cross-reference events across systems that use different timestamp formats
  • Verify that a scheduled job ran at the expected time

How It Works

JavaScript's Date object stores time internally as milliseconds since the Unix epoch. Converting a timestamp to a date uses new Date(timestamp * 1000)(multiplying by 1000 to convert seconds to milliseconds). The Intl.DateTimeFormatAPI formats the result in the selected timezone. Converting a date string back to a timestamp usesDate.parse() divided by 1000.

Frequently Asked Questions

What happens after the year 2038?

The "Year 2038 problem" affects systems that store Unix timestamps as a 32-bit signed integer — it overflows on 19 January 2038. Modern systems use 64-bit integers, which won't overflow for about 292 billion years.

Does the Unix timestamp account for timezones?

No. A Unix timestamp always represents a moment in UTC. Timezone conversion happens only at the display layer — the underlying number is the same everywhere in the world at the same instant.

Is the timestamp in seconds or milliseconds?

The original Unix standard uses seconds. JavaScript's Date.now() returns milliseconds. Many modern APIs (including some databases) use milliseconds. A 13-digit timestamp is almost certainly in milliseconds; a 10-digit one is in seconds.

What is a Unix timestamp? A Unix timestamp is the number of seconds elapsed since January 1, 1970 00:00:00 UTC (the Unix epoch).

Timestamps with 13 digits are in milliseconds. All conversions happen locally in your browser — no data is sent anywhere.