Seconds or milliseconds?

We auto-detect — 10-digit input is seconds, 13-digit is milliseconds.

How's the relative time computed?

Using date-fns — accurate across timezones and DST transitions.

Convert between Unix timestamps, ISO 8601, and human dates — with timezone support.

Paste, drop a file, or .

Timezone

1
Paste a timestamp or date
1700000000, 1700000000000, or '2024-01-15T12:00:00Z'.
2
Pick a timezone
For the human-formatted line.

Seconds or milliseconds?: We auto-detect — 10-digit input is seconds, 13-digit is milliseconds.
How's the relative time computed?: Using date-fns — accurate across timezones and DST transitions.