Unix Timestamp Converter: Epoch Time to Date and Date to Epoch

What is a Unix timestamp?

A Unix timestamp, also called epoch time or POSIX time, is the number of seconds that have passed since 1 January 1970 at 00:00:00 UTC, a moment known as the Unix epoch. It stores a point in time as a single number, which is easy to store, sort and compare, and it does not depend on a time zone, so the same timestamp means the same moment everywhere in the world.

Operating systems, databases, programming languages, logs and APIs use Unix time constantly. Some systems store seconds, while others, including JavaScript, store milliseconds, which is why timestamps with 10 digits and 13 digits are both common.

How to convert a timestamp

1. Enter a Unix timestamp in the first box, in seconds or milliseconds. The tool detects the unit for you.
2. Read the date in UTC, ISO 8601, your local time and a relative form such as 3 days ago.
3. To go the other way, pick a date and time and choose whether it is local time or UTC.
4. Copy the timestamp in seconds or milliseconds.

Seconds or milliseconds?

A timestamp in seconds currently has 10 digits, such as 1760000000. A timestamp in milliseconds has 13 digits, such as 1760000000000. Programming languages differ: JavaScript's Date.now returns milliseconds, Python's time.time returns seconds as a decimal, and PHP's time returns seconds. This converter treats any number at or above 100 billion as milliseconds, which covers the usual cases.

UTC, local time and time zones

A timestamp itself has no time zone. When you convert it to a date, the zone decides what clock time you see. UTC is the standard for servers and logs, and ISO 8601 is the unambiguous text format, such as 2026-10-14T08:30:00.000Z, where Z means UTC. The local time shown here follows your device's time zone, including daylight saving.

The year 2038 problem

Older systems store Unix time in a signed 32-bit integer, which can hold seconds only up to 2,147,483,647. That value corresponds to 03:14:07 UTC on 19 January 2038. One second later such a counter would overflow and wrap to a date in 1901. Modern systems use 64-bit time, which will not overflow for hundreds of billions of years, but old software and embedded devices may still need updating.

Getting the current timestamp in popular languages

• JavaScript: Date.now() returns milliseconds, and Math.floor(Date.now() / 1000) returns seconds.
• Python: int(time.time()) returns seconds.
• PHP: time() returns seconds.
• Java: System.currentTimeMillis() returns milliseconds.
• Go: time.Now().Unix() returns seconds.
• PostgreSQL: EXTRACT(EPOCH FROM now()). MySQL: UNIX_TIMESTAMP().
• Linux and macOS shell: date +%s.

Common timestamp mistakes

• Mixing seconds and milliseconds. A date in the year 1970 usually means a millisecond value was treated as seconds, and a date in the far future means the opposite.
• Forgetting the time zone when you convert a date to a timestamp. The same clock time gives different timestamps in different zones.
• Assuming days are always 86,400 seconds in local time. Daylight saving changes make some local days 23 or 25 hours long, while Unix time itself ignores them.
• Thinking timestamps cannot be negative. Dates before 1970 are valid and are stored as negative numbers.

Famous Unix timestamps

Frequently Asked Questions