Free tool
Unix Timestamp Converter
Convert epoch seconds or milliseconds to a readable date, and back again.
Paste a Unix timestamp to see it as a readable date in UTC, in your local timezone and in ISO 8601, plus how long ago or how far ahead it is. You can also go the other way and turn a date into an epoch value. Everything runs in your browser tab.
A Unix timestamp counts the seconds since 1 January 1970 UTC, ignoring leap seconds. The common trap is scale: JavaScript, Java and most JSON APIs use milliseconds, while Postgres, Python, Go and Unix tools use seconds. Get it wrong by a factor of 1000 and 2026 becomes 1970. This tool guesses the scale from the digit count and tells you which it used.
How to use it
- Paste a timestamp into the input. Ten digits is read as seconds, thirteen as milliseconds.
- Read the UTC, local and ISO 8601 conversions underneath.
- Pick a different timezone to see the same instant elsewhere.
- Or use the date field to convert a date back into an epoch value.
Frequently asked questions
Is my timestamp in seconds or milliseconds?
Count the digits. A present-day timestamp in seconds has 10 digits, and in milliseconds it has 13. If a date comes out in 1970 you passed milliseconds to something expecting seconds; if it lands tens of thousands of years in the future, you did the reverse.
What is the year 2038 problem?
Systems that store the timestamp in a signed 32-bit integer overflow on 19 January 2038, wrapping to 1901. Anything storing it in 64 bits is unaffected, which covers most modern software, but old C code and some embedded systems still care.
Do Unix timestamps have a timezone?
No. A timestamp is an absolute instant, always counted from UTC. The timezone only matters when you format it for a human, which is why the same timestamp shows different wall-clock times in the list below.
Why does my date look one day off?
Almost always a timezone boundary. A timestamp near midnight UTC falls on the previous or next calendar day in another zone. Compare the UTC row with the local row here and the offset will explain it.
The desktop version
Unix Timestamp Converter in Toolbelt
This page does the job in a browser tab. Toolbelt is the same tool as a native Mac app, plus the things a web page cannot do.
Tools
{
"name": "Holizmi",
"tools": [
"json",
"jwt",
"base64"
],
"live": true
}{
"sub": "12345",
"name": "Henry",
"exp": 1767225600
}019bd4e2-7a10-7c3e-9f21-4a6b8d3e5c07
019bd4e2-7a11-7b8a-8e44-1c2f9a7d6b13
019bd4e2-7a12-7d5f-b0c9-7e3a1f8c2d95 1 1 one
2 2 two
3 + inserted
3 4 three- Convert a whole column of timestamps pasted from a spreadsheet
- Keeps your working timezone between sessions
- Convert whatever is on the clipboard with one shortcut
- Works with no connection, so it is reliable on a plane