What is a Unix timestamp?
A Unix timestamp (also called epoch time or POSIX time) is the number of seconds since 00:00:00 UTC on 1 January 1970, “the Unix epoch”. For example, 1760270400 is 12:00 UTC on 12 October 2025. Computers use timestamps because they are simple numbers that are the same in every time zone and easy to compare and sort.
Many systems use smaller units: JavaScript’s Date.now() and Java use milliseconds, while some databases and tracing tools use microseconds or nanoseconds.
How to use the converter
- Timestamp to date: paste a timestamp. The unit is detected from its size, and you see the date in UTC and your local time zone, how long ago it was, and the same moment in other units.
- Date to timestamp: type an ISO 8601 date or use the date picker. Dates without a time zone are read in your local time unless you tick Dates without a time zone are UTC.
- Every result has a copy button. Digit separators such as
1,760,270,400are accepted.
Getting the current timestamp in code
| Language | Seconds | Milliseconds |
|---|---|---|
| JavaScript | Math.floor(Date.now() / 1000) | Date.now() |
| Python | int(time.time()) | time.time_ns() // 1_000_000 |
| Java | Instant.now().getEpochSecond() | System.currentTimeMillis() |
| PHP | time() | (int) (microtime(true) * 1000) |
| Go | time.Now().Unix() | time.Now().UnixMilli() |
| Bash | date +%s | date +%s%3N |
| SQL (PostgreSQL) | extract(epoch from now()) | — |
Limitations
- Dates are shown in UTC and in your device’s time zone. Other time zones are not offered yet.
- Browsers store times to the millisecond, so microsecond and nanosecond timestamps are rounded to the nearest millisecond.
- Only ISO 8601 dates are accepted as text, because other formats such as 03/04/2026 are ambiguous.
Frequently asked questions
How do I know if my timestamp is in seconds or milliseconds?
Count the digits. Timestamps for dates between 2001 and 2286 have 10 digits in seconds and 13 in milliseconds. Microseconds have 16 digits and nanoseconds 19. The converter detects the unit automatically from the size of the number, and you can override it.
What is the Year 2038 problem?
Older systems store Unix time as a signed 32-bit number of seconds, which runs out at 03:14:07 UTC on 19 January 2038 and then wraps around to 1901. Modern systems use 64-bit time, which will not overflow for billions of years. The converter warns you when a timestamp is beyond the 32-bit range.
Do Unix timestamps include leap seconds?
No. Unix time treats every day as exactly 86,400 seconds and ignores leap seconds, so it is not a perfect count of elapsed seconds. This rarely matters outside scientific and some financial uses.
Does a Unix timestamp have a time zone?
No. A Unix timestamp is the same everywhere in the world: it counts seconds since 1 January 1970 at midnight UTC. Time zones only matter when you turn it into a calendar date and time, which is why the converter shows both UTC and your local time.