The static method returns the number of milliseconds elapsed since January 1, 1970 00:00:00 UTC.


var timeInMs =;

Return value

A Number representing the milliseconds elapsed since the UNIX epoch.


This method was standardized in ECMA-262 5th edition. Engines which have not been updated to support this method can work around the absence of this method using the following shim:

if (! { = function now() {
    return new Date().getTime();


Reduced time precision

To offer protection against timing attacks and fingerprinting, the precision of might get rounded depending on browser settings.
In Firefox, the privacy.reduceTimerPrecision  preference is enabled by default and defaults to 20µs in Firefox 59; in 60 it will be 2ms.

// reduced time precision (2ms) in Firefox 60
// 1519211809934
// 1519211810362
// 1519211811670
// ...

// reduced time precision with `privacy.resistFingerprinting` enabled;
// 1519129853500
// 1519129858900
// 1519129864400
// ...

In Firefox, you can also enable privacy.resistFingerprinting, the precision will be 100ms or the value of privacy.resistFingerprinting.reduceTimerPrecision.microseconds, whichever is larger.


ECMAScript (ECMA-262)
The definition of '' in that specification.

Browser compatibility

BCD tables only load in the browser

See also