Unix timestamp converter
Paste a Unix timestamp to see it as a UTC, ISO 8601 and local date, or type a date to get its timestamp; seconds and milliseconds are detected automatically.
🔒 Runs entirely in your browser. Nothing you paste is uploaded or sent to a server.
Timestamp → date
Date → timestamp
What a Unix timestamp is
A Unix timestamp (epoch time) is the number of seconds since 1970-01-01 00:00:00 UTC, ignoring leap seconds. It has no time zone: the same instant has the same timestamp everywhere, and only the display changes with your location.
| Digits | Unit | Example | Used by |
|---|---|---|---|
| 10 | seconds | 1700000000 |
Unix, date +%s, PHP, Python int(time.time()), JWT exp |
| 13 | milliseconds | 1700000000000 |
JavaScript Date.now(), Java System.currentTimeMillis() |
| 16 | microseconds | 1700000000000000 |
Python time.time_ns()//1000, PostgreSQL internals |
| 19 | nanoseconds | 1700000000000000000 |
Go UnixNano(), time.time_ns() |
This converter guesses the unit from the size of the number. A classic bug is passing seconds to something that expects milliseconds, which gives a date in January 1970; the reverse gives a date tens of thousands of years in the future.
Getting the current timestamp
| Language | Seconds | Milliseconds |
|---|---|---|
| Shell | date +%s |
date +%s%3N |
| JavaScript | Math.floor(Date.now()/1000) |
Date.now() |
| Python | int(time.time()) |
time.time_ns() // 1_000_000 |
| Go | time.Now().Unix() |
time.Now().UnixMilli() |
| SQL (PostgreSQL) | extract(epoch from now()) |
To convert in the shell: date -u -d @1700000000 (GNU) or date -u -r 1700000000 (macOS).
Clocks and certificate errors
A wrong system clock breaks TLS: certificates have notBefore/notAfter timestamps, so a machine whose clock is years off rejects valid certificates with errors like curl: (60) SSL certificate problem or CERTIFICATE_VERIFY_FAILED. Compare the live clock above with the server's date -u output. The year 2038 problem affects systems storing seconds in a signed 32-bit integer, which overflows at 2147483647 (2038-01-19 03:14:07 UTC).
Last updated 2026-11-01.