Date.prototype.setSeconds()
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
ThesetSeconds() method ofDate instances changes the seconds and/or milliseconds for this date according to local time.
Try it
const event = new Date("August 19, 1975 23:15:30");event.setSeconds(42);console.log(event.getSeconds());// Expected output: 42console.log(event);// Expected output: "Sat Apr 19 1975 23:15:42 GMT+0100 (CET)"// Note: your timezone may varySyntax
setSeconds(secondsValue)setSeconds(secondsValue, msValue)Parameters
secondsValueAn integer between 0 and 59 representing the seconds.
msValueOptionalAn integer between 0 and 999 representing the milliseconds.
Return value
Changes theDate object in place, and returns its newtimestamp. If a parameter isNaN (or other values that getcoerced toNaN, such asundefined), the date is set toInvalid Date andNaN is returned.
Description
If you do not specify themsValue parameter, the value returnedfrom thegetMilliseconds() method isused.
If a parameter you specify is outside of the expected range,setSeconds()attempts to update the date information in theDate object accordingly.For example, if you use 100 forsecondsValue, the minutes storedin theDate object will be incremented by 1, and 40 will be used forseconds.
BecausesetSeconds() operates on the local time, crossing a Daylight Saving Time (DST) boundary may result in a different elapsed time than expected. For example, if setting the seconds crosses a spring-forward transition (losing an hour), the difference in timestamps between the new and old date is one hour less than the nominal time difference. Conversely, crossing a fall-back transition (gaining an hour) result in an extra hour. If you need to adjust the date by a fixed amount of time, consider usingsetUTCSeconds() orsetTime().
If the new local time falls within an offset transition, the exact time is derived using the same behavior asTemporal'sdisambiguation: "compatible" option. That is, if the local time corresponds to two instants, the earlier one is chosen; if the local time does not exist (there is a gap), we go forward by the gap duration.
Examples
Using setSeconds()
const theBigDay = new Date();theBigDay.setSeconds(30);Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-date.prototype.setseconds |