Decode a JSON Web Token, check its claims and expiry, flag risks, and verify HS, RS, PS, ES or EdDSA signatures.
Unix Timestamp Converter
Convert Unix timestamps to dates and back, in UTC, South African time or your local time zone.
Runs in your browser — nothing you enter is sent to our servers
How it works
Timestamp → date: values of 13 or more digits are treated as milliseconds, shorter values as seconds. The instant is then shown in UTC, in SAST (UTC+2) and in your device’s time zone, plus ISO 8601 and a relative description (“3 days ago”).
Date → timestamp: the date and time are interpreted in the time zone you choose, then converted to seconds and milliseconds since 1 January 1970 UTC.
Example
1767225600 is 1 January 2026, 00:00:00 UTC — which is 02:00 on 1 January in South Africa. Going the other way, midnight on 1 January 2026 in SAST is 1767218400, two hours (7,200 seconds) earlier.
Frequently asked questions
What is a Unix timestamp?
The number of seconds since 00:00:00 UTC on 1 January 1970 (the Unix epoch), not counting leap seconds. Many systems use milliseconds instead — the converter detects which you entered.
What time zone is South Africa in?
South African Standard Time (SAST) is UTC+2 all year — South Africa doesn’t use daylight saving time. The converter shows SAST alongside UTC and your device’s own time zone.
What is the year 2038 problem?
Systems that store timestamps as signed 32-bit integers overflow after 03:14:07 UTC on 19 January 2038 (timestamp 2,147,483,647). Modern 64-bit systems are not affected.
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