Unix timestamp converter
1790809200
seconds since 1 January 1970 UTC, right now
Timestamp to date
Thursday 1 October 2026 at 00:00:00 BST
- UTC: Wednesday 30 September 2026 at 23:00:00 UTC
- ISO 8601:
2026-09-30T23:00:00Z - Read as seconds
Date to timestamp
1790809200
- Milliseconds: 1790809200000
- Thursday 1 October 2026 at 00:00:00 BST
How to use it
- The large number is the current Unix time, counting up every second.
- Paste a timestamp into the first box. Ten digits are read as seconds and 13 digits as milliseconds; the result shows UK time, UTC and ISO 8601.
- To go the other way, enter a date and time and choose UK time or UTC.
- To share a conversion, add
?t=and the timestamp to the address, for example/unix-timestamp/?t=2147483647.
What Unix time is
Unix time counts the seconds since the "epoch", 00:00:00 UTC on Thursday 1 January 1970, the date chosen by the designers of the Unix operating system. The POSIX standard defines every day as exactly 86,400 seconds, so leap seconds are not counted. Because it is based on UTC, a timestamp means the same moment everywhere: time zones and clock changes only matter when you turn it into a local date.
Worked example: 1790809200 seconds is 20,726 days and 23 hours after the epoch, which is 23:00 UTC on Wednesday 30 September 2026. The UK is on British Summer Time that day, so it is midnight at the start of Thursday 1 October 2026 in London.
Seconds, milliseconds and ISO 8601
Unix tools, PHP, Python's time.time() and most databases use seconds. JavaScript's Date.now() and Java use milliseconds, which add three digits. Logs and APIs often use ISO 8601 instead, such as 2026-09-30T23:00:00Z, where the Z means UTC. Negative timestamps are dates before 1970: -86400 is 31 December 1969.
The year 2038 problem
Older systems store Unix time in a signed 32-bit integer, which tops out at 2,147,483,647: 03:14:07 UTC on Tuesday 19 January 2038. One second later the count wraps round to a large negative number, which those systems read as 13 December 1901. Modern operating systems and languages use 64-bit time, which will not run out for billions of years, but embedded devices and old file formats can still be affected. Enter 2147483647 above to see the moment.
UK time and the epoch
Timestamp 0 shows as 1am, not midnight, in UK time. On 1 January 1970 the UK was in the middle of the British Standard Time trial and kept GMT+1 all year; see British Summer Time for the story. Today the UK is on GMT in winter, so timestamps from late October to late March match UTC exactly. To convert between other zones, use the time zone converter.
Frequently asked questions
What is a Unix timestamp?
The number of seconds since 00:00:00 UTC on Thursday 1 January 1970, not counting leap seconds. It is the same everywhere in the world at a given moment, whatever the local time zone.
How do I tell seconds from milliseconds?
Count the digits. A timestamp for a date between 2001 and 2286 has 10 digits in seconds and 13 digits in milliseconds. JavaScript and Java use milliseconds; most databases, Unix tools and PHP use seconds.
What is the year 2038 problem?
Systems that store the timestamp as a signed 32-bit number can only count up to 2,147,483,647, which is 03:14:07 UTC on Tuesday 19 January 2038. One second later the number overflows and can be read as a date in December 1901. Systems using 64-bit time are not affected.
Does a Unix timestamp change when the clocks go back?
No. The timestamp counts real seconds in UTC, so it carries on steadily through British Summer Time changes. Only the local time it is converted to jumps.
Why does 1 January 1970 show as 1am in the UK?
Because the UK was trialling British Standard Time, one hour ahead of GMT all year, from October 1968 to October 1971. Timestamp 0 is midnight UTC, which was 1am in the UK.