Unix Timestamp Converter

What the Unix timestamp converter does

Computers often store time as a single number: the count of seconds since the start of 1970 in UTC. It’s compact and easy to compare, but a value like 1700000000 means nothing at a glance. This converter turns timestamps into readable dates in your own time zone and in UTC, and turns a date you pick back into a timestamp.

You’ll find it useful when reading server logs, debugging a database column, checking when an API token expires, or setting a scheduled job to run at an exact moment. The live clock at the top is a quick source for “now” when you need it in a test or a query.

How to use the Unix timestamp converter

1. The top panel shows the current Unix time, updated every second. Pause it or copy the seconds value with one click.
2. Paste a timestamp in Timestamp to date. Seconds, milliseconds, microseconds and nanoseconds are detected from the size of the number, or you can choose the unit yourself.
3. In Date to timestamp, pick a date and time and choose whether it is in your time zone or UTC.

Understanding the results

For each timestamp you get several views of the same moment: your local time with the name of the zone your device reports, the UTC time, the ISO 8601 form many APIs use, and a relative description such as “3 days ago” or “in 2 hours”. The seconds and milliseconds values are listed too, so you can switch between the two styles without doing the maths. When the unit is detected automatically, a note says which one was assumed.

When converting a date to a timestamp, the time zone choice matters. The same clock time in London and in Nassau gives two timestamps several hours apart. If a scheduled task fires at the wrong hour, the usual cause is a local time entered where UTC was expected, or the reverse. The timestamp box also accepts decimals, and negative numbers for dates before 1970.

Questions

What is a Unix timestamp?

The number of seconds since 00:00:00 UTC on 1 January 1970, not counting leap seconds. It is the same everywhere in the world at a given moment.

Seconds or milliseconds?

Most Unix tools use seconds (10 digits today). JavaScript and many APIs use milliseconds (13 digits).

What is the year 2038 problem?

Systems that store the timestamp in a signed 32-bit integer overflow on 19 January 2038. Modern systems use 64 bits.

Why was my timestamp read in the wrong unit?

Automatic detection goes by size, so very early dates are ambiguous. A millisecond value from before March 1973 is small enough to look like seconds. Pick the unit from the list and the result updates.