Unix Timestamp Converter

What a Unix timestamp is

A Unix timestamp counts the seconds that have passed since a fixed moment called the Unix epoch: midnight UTC on 1 January 1970. The number 0 is that moment, 86400 is exactly one day later, and a negative number is a moment before 1970. Because it is a single plain number with no time zone and no calendar attached, it is how most databases, log files, APIs, cookies and JSON Web Tokens record time. The same timestamp names the same instant everywhere on Earth; only the way you display it changes from place to place.

You need a converter whenever a raw number meets a human: an API response with "created_at": 1700000000, an exp claim in a token that seems to expire too early, a log line from a server in another country, or a database column you are trying to filter by date.

How to use it

• Timestamp to date: paste the number. The tool shows the instant in your device's own time zone, in UTC, in India Standard Time, in ISO 8601 form, and relative to now, such as "3 days ago".
• Date to timestamp: pick a date, type a 24 hour time and say which time zone that clock time is in. You get the timestamp in seconds and in milliseconds.
• The Current Unix time box ticks every second; press Copy to grab the value.

Seconds or milliseconds?

Unix tools and most server languages, including PHP's time() and Python's time.time(), count seconds. JavaScript's Date.now() and Java's System.currentTimeMillis() count milliseconds, a number a thousand times larger. The tool guesses from the length of the number: up to 11 digits is read as seconds, 12 to 14 digits as milliseconds, and longer numbers as microseconds or nanoseconds. Today a seconds value has 10 digits and a milliseconds value has 13. The guess is wrong for millisecond values before March 1973, which have 11 digits or fewer; choose the unit by hand for those.

A worked example

Enter 1700000000. It is read as seconds and shows Tuesday 14 November 2023 at 22:13:20 UTC. In India, five and a half hours ahead, the same instant is already Wednesday 15 November at 03:43:20. That date change is why a report built on UTC can put an Indian evening sale on the wrong day. Enter 1700000000000 and you get the same instant, read as milliseconds.

The year 2038 problem

Many older systems store the timestamp as a signed 32 bit integer, whose largest value is 2,147,483,647. That is reached at 03:14:07 UTC on 19 January 2038, after which such a counter wraps around to a date in December 1901. Modern 64 bit systems are not affected, but embedded devices, old file formats and some databases still are. If a converted timestamp lies beyond that limit, the tool points it out.

Limits and privacy

Unix time ignores leap seconds, so every day is exactly 86,400 seconds, the same convention your computer uses. Very old dates are shown in the Gregorian calendar extended backwards, even before countries adopted it, so a historical date may not match the calendar people used at the time. Local time comes from your device's time zone setting. All conversions run in your browser, and Ur Next Door never sees the timestamps you enter.