Timestamp Converter
Convert a Unix timestamp to a readable date, or a date to a Unix timestamp — both directions
update live as you type, computed by your browser's own clock and Date
engine.
Batch mode
Why convert timestamps in the browser?
A Unix timestamp on its own is rarely sensitive, but it's almost always sitting right next to something that is — a log line, a database row, a session record. Nothing you paste here is ever sent to a server — see why that matters. Seconds vs. milliseconds is detected automatically from the number of digits, and every result — ISO, UTC, local time, and relative time — is recomputed instantly as you type.
FAQ
What exactly is a Unix timestamp?
The number of seconds (or milliseconds, depending on the system) since
1970-01-01T00:00:00Z, the Unix epoch. It's
POSIX time, which by convention ignores leap seconds — every day is treated as exactly
86,400 seconds.
How does it know if I pasted seconds or milliseconds?
By digit count: 10-digit values are treated as seconds (valid until the year 2286), 13-digit values as milliseconds. This is a heuristic, not a guarantee — a timestamp near the 1970 epoch in milliseconds could have fewer digits and be misread as seconds. If the detected unit looks wrong, that's why.
Why is "Local" different from "UTC"?
Local time reflects your own browser/OS timezone setting, not any server's. If you paste an
ISO 8601 string with an explicit offset (e.g. +05:30),
that's respected; a date-only or offset-less string follows the same UTC-vs-local parsing
rules as JavaScript's own Date constructor,
which is a well-known source of off-by-one-day bugs if you're not expecting it.