| Event | Timestamp | Date (UTC) |
|---|
A Unix timestamp (also known as Epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC, excluding leap seconds. It is used universally in computing because it provides a timezone-independent, language-neutral way to represent a moment in time as a single integer. Databases, APIs, log files, JWT tokens, and file systems all use Unix timestamps extensively. The 32-bit timestamp overflow (the "Year 2038 problem") will occur on January 19, 2038 at 03:14:07 UTC, when the signed 32-bit integer overflows.
JavaScript uses millisecond timestamps (Date.now()), while Unix/Python/PHP use second-precision timestamps. This tool automatically detects whether you've entered a seconds or milliseconds timestamp. Common operations include converting API response timestamps for display, debugging JWT expiration times, and comparing log entries across systems in different timezones.