How do millisecond timestamps differ from second timestamps?

A milliseconds timestamp is exactly 1000 times larger than the equivalent seconds timestamp. For example, the seconds timestamp 1700000000 is 1700000000000 in milliseconds.

How do I tell if a timestamp is in seconds or milliseconds?

Timestamps in seconds are around 10 digits long (e.g. 1700000000). Millisecond timestamps are 13 digits long (e.g. 1700000000000). If the value is greater than 9,999,999,999 it is likely in milliseconds.

Millisecond timestamp to date

Enter a Unix timestamp in milliseconds (as returned by JavaScript's Date.now()) to see the equivalent date and time. Also converts to the standard seconds-based timestamp.

Enter a value above to convert

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Runs entirely in your browser

How it works

All conversions use the browser's native Date API: new Date(), .toISOString(), .toLocaleString(), and Date.now(). No server processing, the result appears immediately in your browser.

Processing runs in your browser

Timestamps are converted entirely in your browser tab. Our servers are not involved at any point.

Related operations

For working out the gap between any two dates, try the date calculator. To find an exact age in years, months, and days, use the age calculator. For aligning timestamps across regions, see the timezone converter.

Frequently asked questions

How do millisecond timestamps differ from second timestamps?: A milliseconds timestamp is exactly 1000 times larger than the equivalent seconds timestamp. For example, the seconds timestamp 1700000000 is 1700000000000 in milliseconds.
How do I tell if a timestamp is in seconds or milliseconds?: Timestamps in seconds are around 10 digits long (e.g. 1700000000). Millisecond timestamps are 13 digits long (e.g. 1700000000000). If the value is greater than 9,999,999,999 it is likely in milliseconds.

Millisecond timestamp to date

How it works

Processing runs in your browser

Related operations

Frequently asked questions

Related tools