Unix Timestamp Converter
Convert a Unix timestamp (seconds or milliseconds since 1 January 1970 UTC) to a readable date, or a date to its timestamp.
Unix time counts seconds since the epoch, 1970-01-01 00:00:00 UTC, ignoring leap seconds.
How the unix timestamp converter works
Unix time counts seconds since the epoch, 1970-01-01 00:00:00 UTC, ignoring leap seconds. Timestamps above 10¹¹ are treated as milliseconds (the JavaScript convention). The date shown is in UTC; local clocks differ by your time-zone offset.
Formula: timestamp = (date − 1970-01-01T00:00Z) in seconds
Worked examples
| Inputs | Result | Note |
|---|---|---|
| 1,800,000,000 | 2027-01-15 08:00:00 UTC | 15 January 2027 08:00 UTC |
| 0 | 1970-01-01 00:00:00 UTC | the epoch, 1 January 1970 |
| 2026-01-01 | 1767225600 | 1,767,225,600 |
FAQFrequently asked questions
What is the Unix epoch?
00:00:00 UTC on 1 January 1970 — the zero point of Unix time.
Seconds or milliseconds?
Unix time is in seconds; JavaScript and many APIs use milliseconds. Values over 10¹¹ are treated as milliseconds here.
What is the year-2038 problem?
Signed 32-bit timestamps overflow at 2,147,483,647 seconds — 19 January 2038. 64-bit systems are unaffected.
Does Unix time include leap seconds?
No — every day is exactly 86,400 seconds.
Why is the date shown in UTC?
Timestamps are time-zone-free; add your local offset to get wall-clock time.
Where these figures come from
- ISO 8601 — Date and time — Representations for information interchange — the yyyy-mm-dd format and the week-numbering rules used here
- US Naval Observatory — Calendars — the Gregorian leap-year rule
- Australian Government — public holidays — public holidays by state (not applied here)
Last checked: September 2026. The Gregorian calendar rules do not change; working-day counts exclude Saturdays and Sundays only.