What is the difference between seconds and milliseconds?

Unix seconds count from 1970-01-01T00:00:00Z. JavaScript's Date uses milliseconds, which is the seconds value times 1,000. The same digits are not the same instant.

Which timezone is local?

The timezone of the browser. UTC and the ISO-8601 Zulu value do not depend on that setting.

What does the relative label mean?

It compares the converted instant with the current time, such as "2 minutes ago".

Unix Timestamp Converter

Turn a Unix timestamp into a calendar time, or a calendar time into seconds and milliseconds. Seconds and milliseconds are separate choices so a 10-digit value is not guessed.

Seconds and milliseconds are different units. 1700000000 seconds and 1700000000000 milliseconds are the same instant. 1700000000 milliseconds is in 1970.

Unix timestamp (seconds)

Date to Unix

ISO-8601

1700000000 seconds · 1700000000000 milliseconds

Reading the current time… A timezone in the date wins over the UTC or Local switch.

How to use it

Choose seconds or milliseconds before you convert a number.
Read UTC, local time, and ISO-8601. Copy either unit.
Use the current time, or convert an ISO-8601 date back to Unix time.

Common mistakes

The unit is not inferred. A 10-digit number read as milliseconds lands in 1970.
A date without Z is UTC in UTC mode and local in Local mode.
If the text already contains Z or an offset, that zone is the instant.

Examples

Seconds

1700000000 seconds → 2023-11-14T22:13:20.000Z

Milliseconds

1700000000000 milliseconds → the same instant. 1700000000 milliseconds is in January 1970.

Frequently asked questions

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