Convert timestamp to date or date to timestamp, compare Unix seconds vs. milliseconds, and verify API, JWT, log, or release-time values without losing timezone context.
Use this when you need a timestamp-to-date check for API payloads, JWT exp or iat claims, logs, and release verification. Detected milliseconds from the submitted value.
A Unix timestamp (also known as epoch time or POSIX time) is a system for describing a point in time. It represents the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC (the Unix epoch), not counting leap seconds. The same concept is often stored in milliseconds by browsers, logs, and APIs.
Unix time is a signed integer that increases by one every second, while many JavaScript and browser workflows store the same moment in milliseconds. The raw value is timezone-independent because it always represents UTC. Converting timestamp to date or date to timestamp becomes accurate once you know the unit and the intended wall-clock offset.
32-bit systems store Unix time in a signed 32-bit integer, which will overflow on January 19, 2038. Most modern systems use 64-bit integers, which won't overflow for billions of years.
Timestamps are timezone-independent, take less storage, are easy to compare and calculate with, and avoid parsing ambiguities that can occur with date string formats.