Unix Timestamp Converter
Enter a Unix timestamp to convert it to a human-readable date and time, or enter a date to find its Unix timestamp — the number of seconds since January 1, 1970 (UTC), commonly used in programming, databases, and APIs.
How the Unix Timestamp Converter formula works
Unix time counts seconds elapsed since the epoch:
Unix timestamp = seconds elapsed since January 1, 1970 00:00:00 UTC Date = Epoch + Unix timestamp (in seconds)
Step-by-step calculation
- To convert a timestamp to a date: add the timestamp (in seconds) to the epoch start date.
- To convert a date to a timestamp: calculate the number of seconds elapsed between the epoch and that date.
Worked example
The Unix timestamp 1735689600 converts to January 1, 2025 00:00:00 UTC — a round number often used as a reference point in testing and documentation.
Frequently asked questions
Why does Unix time start at 1970?
January 1, 1970 was chosen as an arbitrary reference point (the 'epoch') by early Unix system developers, and it became a widely adopted standard across computing systems ever since.
Are Unix timestamps always in seconds?
Traditionally yes, but some systems (like JavaScript's Date.now()) use milliseconds instead — if a timestamp looks unusually large (13 digits instead of 10), it's likely in milliseconds and needs dividing by 1,000 first.