Event.timeStamp

The timeStamp read-only property of the Event interface returns the time (in milliseconds) at which the event was created.

Note: This property only works if the event system supports it for the particular event.

Syntax

time = event.timeStamp;

Value

This value is the number of milliseconds elapsed from the beginning of the current document's lifetime till the event was created.

In newer implementations, the value is a DOMHighResTimeStamp accurate to 5 microseconds (0.005 ms). In older implementations, the value is a DOMTimeStamp, accurate to a millisecond.

Example

HTML

<p>
  Focus this iframe and press any key to get the
  current timestamp for the keypress event.
</p>
<p>timeStamp: <span id="time">-</span></p>

JavaScript

function getTime(event) {
  var time = document.getElementById("time");
  time.firstChild.nodeValue = event.timeStamp;
}
document.body.addEventListener("keypress", getTime);

Result

Reduced time precision

To offer protection against timing attacks and fingerprinting, the precision of Event.timeStamp might get rounded depending on browser settings.

In Firefox, the privacy.reduceTimerPrecision preference is enabled by default and defaults to 20us in Firefox 59; in 60 it will be 2ms.

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


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

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

Specifications

Specification Status Comment
DOM
The definition of 'Event.timeStamp' in that specification.
Living Standard

Browser compatibility

DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
timeStampChrome Full support 49
Notes
Full support 49
Notes
Notes Starting with Chrome 49, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
Edge Full support 12Firefox Full support Yes
Notes
Full support Yes
Notes
Notes Starting with Chrome 49, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
IE Full support Yes
Notes
Full support Yes
Notes
Notes Starting with Chrome 49, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
Opera Full support 36
Notes
Full support 36
Notes
Notes Starting with Chrome 49, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
Safari Full support YesWebView Android Full support 49
Notes
Full support 49
Notes
Notes Starting with version 49, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
Chrome Android Full support 49
Notes
Full support 49
Notes
Notes Starting with Chrome 49, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
Firefox Android Full support Yes
Notes
Full support Yes
Notes
Notes Starting with Chrome 49, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
Opera Android Full support 36
Notes
Full support 36
Notes
Notes Starting with Chrome 49, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.
Safari iOS Full support YesSamsung Internet Android Full support 5.0
Notes
Full support 5.0
Notes
Notes Starting with Samsung Internet 5.0, Firefox 54 and Opera 36, this property returns DOMHighResTimeStamp instead of DOMTimeStamp.

Legend

Full support
Full support
See implementation notes.
See implementation notes.