0Unix seconds
UTCThu, 01 Jan 1970 00:00:00 GMT
ISO 86011970-01-01T00:00:00.000Z
Local1969-12-31, 5:00:00 p.m.

Unix Timestamp

Type a timestamp — unit (s/ms/μs/ns) detected automatically.

Human Date → Timestamp

Time Difference

Enter two timestamps, ISO 8601 dates, or UTC strings — format is detected automatically.

Time Reference

IntervalSecondsMilliseconds
1 Minute6060,000
1 Hour3,6003,600,000
1 Day86,40086,400,000
1 Week604,800604,800,000
1 Month (avg)2,629,7462,629,746,000
1 Year (avg)31,556,95231,556,952,000

What is a Unix Timestamp?

A Unix timestamp (also called Epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC — known as the Unix Epoch. It is a timezone-independent, language-agnostic way to represent a point in time.

  • Negative values represent dates before January 1, 1970
  • Stored as a simple integer — no timezone ambiguity
  • Universally supported across all programming languages
  • Millisecond and microsecond variants are common in modern APIs

The Year 2038 Problem

Systems that store Unix timestamps as a signed 32-bit integer can only represent dates up to January 19, 2038, 03:14:07 UTC. After that point the value overflows and wraps to a large negative number — representing a date in 1901.

  • Max 32-bit signed value: 2,147,483,647
  • Affects legacy C programs, databases, and embedded systems
  • 64-bit systems are not affected — they can handle dates billions of years into the future
  • Most modern systems have migrated to 64-bit timestamps

Common Date Formats

  • ISO 86012026-03-11T22:00:00Z — the international standard
  • RFC 2822Wed, 11 Mar 2026 22:00:00 +0000 — used in email headers
  • RFC 3339 — a strict profile of ISO 8601 used in internet protocols
  • Unix seconds1741737600 — most compact, no timezone
  • Unix milliseconds1741737600000 — used by JavaScript's Date.now()