Unix timestamp converter

What it does

A Unix timestamp converter turns a number such as 1793268000 into a date you can read, and turns a date back into a number you can store. Paste a value in seconds or milliseconds and you get ISO 8601, RFC 2822, the time in any IANA timezone, your browser's local time and a relative phrase such as "in 3 hours". There is also a date picker for the reverse direction, interpreted in whichever timezone you choose, so you can produce the exact timestamp an API or cron job expects.

How to use it

1. Paste the timestamp. Spaces, commas and underscores are ignored.
2. Leave the unit on automatic unless you know the value is unusual; ten digits are read as seconds, thirteen as milliseconds.
3. Choose a timezone. Asia/Kolkata, Asia/Dubai and UTC are the common picks for our clients.
4. Copy the format you need with the button beside it.
5. To go the other way, pick a date and time in the lower field; the matching seconds and milliseconds appear under it.

How to read the result

Take 1793268000. Read as seconds, that is 29 October 2026 at 10:00:00 UTC, so the ISO line reads 2026-10-29T10:00:00.000Z. In Asia/Kolkata the same instant is 15:30, because India is UTC+05:30 all year. In Europe/London it is 10:00, since British Summer Time ended four days earlier and the offset is back to zero.

The milliseconds figure is simply the seconds multiplied by 1,000, so 1793268000000. If you pass a seconds value where JavaScript expects milliseconds you will land in January 1970, which is the usual reason a date shows up as 1970.

The RFC 2822 line is the format used in email headers and older HTTP responses. The day-of-year figure is handy when checking log rotation or billing periods. The relative phrase updates every second, so a value a few minutes ahead counts down as you watch.

We handle this kind of time handling in web app development projects every week; a related helper is the cron expression generator for scheduling the jobs that produce these timestamps.