What is a Unix timestamp?
A Unix timestamp counts the seconds since 1 January 1970 at 00:00 UTC. Computers, databases and APIs use it because it is one plain number that means the same moment everywhere. Many systems, including JavaScript and Java, count milliseconds instead, which gives a 13-digit number.
How the converter works
Type a timestamp and the tool shows the exact date in your local time, in UTC and in any city you choose. With Detect automatically, numbers below 100 billion are read as seconds and larger ones as milliseconds. To go the other way, pick a date and time and read the seconds and milliseconds.
Good to know
- Timestamps never carry a time zone. The zone only matters when you display the date.
- 16-digit values are usually microseconds, so divide by 1,000 first.
- Working with deadlines? Try the date difference calculator or the time zone converter.
Frequently asked questions
What is the current Unix timestamp?
It is shown at the top of the tool and updates every second. It is the number of seconds since 1 January 1970 UTC.
How do I tell seconds from milliseconds?
A timestamp for a date today has 10 digits in seconds (for example 1700000000) and 13 digits in milliseconds (1700000000000). The automatic option uses that rule.
What is the Year 2038 problem?
Systems that store the timestamp in a signed 32-bit number run out on 19 January 2038 at 03:14:07 UTC. Modern 64-bit systems are not affected.
Does a Unix timestamp include a time zone?
No. It always counts from UTC. Local time is only worked out when the number is shown as a date.
Are leap seconds counted?
No. Unix time pretends every day has exactly 86,400 seconds, so leap seconds are skipped.