Timestamp Converter

A Unix timestamp (also called Epoch time) is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC. It is a widely used standard for representing time in computing because it is timezone-independent and easy to compare.

A Unix timestamp in seconds is typically 10 digits (e.g. 1700000000), while milliseconds timestamps are 13 digits (e.g. 1700000000000). JavaScript's Date.now() returns milliseconds. This tool auto-detects which format you provide.

ISO 8601 is an international standard for date/time representation. It looks like 2024-01-15T14:30:00.000Z. The 'T' separates date and time, and 'Z' indicates UTC. It is unambiguous and widely used in APIs and data interchange.

Systems storing Unix timestamps as 32-bit signed integers will overflow on January 19, 2038 at 03:14:07 UTC. Modern systems use 64-bit integers, which can represent dates billions of years into the future, effectively solving this problem.

Unix timestamps are always in UTC and are not affected by timezones. The same moment in time has the same Unix timestamp everywhere in the world. Only the human-readable representation changes based on the viewer's timezone.