Timestamp
Unix epoch ↔ human date & relative time
Convert a Unix timestamp (epoch time) to a human-readable date, or convert any date back to epoch seconds or milliseconds — all computed locally in your browser with JavaScript's `Date` object, no server round-trip. Unix time counts the number of seconds (or milliseconds) elapsed since 00:00:00 UTC on January 1, 1970, and is the standard way computers, databases, APIs, and log files store points in time internally, since it's timezone-independent and trivially comparable as a plain number. This tool also shows the live current epoch (updating every second), accepts both 10-digit (seconds) and 13-digit (milliseconds) timestamps, parses free-form date strings, and displays the relative "time ago" / "time from now" alongside ISO 8601, UTC, and your local timezone representation.
What is a Unix timestamp?
It's the number of seconds that have elapsed since the Unix epoch — 00:00:00 UTC on January 1, 1970 — ignoring leap seconds. Negative values represent dates before 1970. It's called "epoch time" or "POSIX time" interchangeably.
Why does my timestamp have 13 digits instead of 10?
10-digit timestamps are in seconds; 13-digit timestamps are in milliseconds (the format JavaScript's `Date.now()` returns). This tool detects the digit count automatically and parses either correctly — paste either format and it'll be recognized.
When will Unix time overflow (the Year 2038 problem)?
Systems that store the timestamp as a signed 32-bit integer will overflow at 2,147,483,647 seconds — 03:14:07 UTC on January 19, 2038. Modern 64-bit systems and JavaScript's `Date` (which uses a 64-bit float in milliseconds) aren't affected; the issue is limited to legacy 32-bit software.
Does Unix time account for time zones?
No — a Unix timestamp is always relative to UTC and has no timezone of its own. The timezone only matters when you format it into a human-readable string, which is why this tool shows both the UTC and your local-timezone rendering side by side.