Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and times, or convert any date and time to a Unix timestamp.
About Unix Timestamps
A Unix timestamp (also called Epoch time or POSIX time) is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970 — known as the Unix Epoch. It is the most widely used time format in computer systems, databases, APIs, and log files because it is timezone-independent, sortable as a plain integer, and easy to calculate differences with.
Seconds vs milliseconds
Classic Unix timestamps count in seconds. Many modern systems and JavaScript in particular use milliseconds (multiply by 1000). A Unix timestamp in seconds is 10 digits (e.g. 1700000000 = November 2023); in milliseconds it is 13 digits (1700000000000). This distinction matters when parsing timestamps from APIs or logs.
Common conversions
- ISO 8601 — Machine-readable datetime format:
2023-11-14T22:13:20Z. Used in APIs, XML, and RSS feeds. TheZmeans UTC. - RFC 2822 — Email and HTTP date format:
Wed, 14 Nov 2023 22:13:20 +0000 - UTC — Coordinated Universal Time, the timezone-neutral reference time
Year 2038 problem
32-bit signed integers can store Unix timestamps up to 2,147,483,647 — which corresponds to 19 January 2038. Systems still using 32-bit time representations will overflow on that date. Modern 64-bit systems can represent timestamps billions of years into the future. Most modern programming languages and operating systems already use 64-bit time.