How to convert a Unix timestamp to a date (and back)
API logs hand you 1704067200 and expect you to know it means January 1, 2024 at midnight UTC. Paste the number — or a date — and read every representation at once, converted in your browser.
Step by step
Open the Unix timestamp converter
Start the free converter — nothing to install.
Paste the timestamp
Enter the epoch number from your log or API response; surrounding spaces are trimmed automatically.
Check seconds versus milliseconds
A value of 10 or fewer digits is treated as seconds; anything longer is treated as milliseconds — so 1704067200 and 1704067200000 land on the same instant.
Read every view at once
See the instant as ISO 8601, in UTC, and in your device's local time zone side by side.
Or convert a date to a timestamp
Enter a local date and time to get Unix seconds (floored) plus the exact millisecond value for a scheduled job or API call.
Tips that save a second try
The seconds-versus-milliseconds decision is based on digit count, not magnitude — unusual 11-digit second values or short millisecond values can be misread, so check the preview.
Date-to-timestamp follows your device's local time zone; the same wall-clock time yields a different epoch value in another zone.
Enter plain integers: negative values and scientific notation are not interpreted the way you might expect.
Common questions
How does the converter decide between seconds and milliseconds?
By trimmed character count: a timestamp with more than 10 digits is treated as milliseconds, otherwise as seconds — which is then multiplied by 1,000.
Why does the same date give a different timestamp on another device?
The date input has no explicit time-zone selector, so the browser interprets it in that device's local zone before computing the universal epoch value. Timestamp-to-date is unaffected.