Web/API/File/lastModifiedDate

DeprecatedThis feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The File.lastModifiedDate ' read-only property returns the last modified date of the file. Files without a known last modified date returns the current date .

Syntax

var time = instanceOfFile.lastModifiedDate

Value

A Date object indicating the date and time at which the file was last modified.

Example

// fileInput is a HTMLInputElement: <input type="file" multiple id="myfileinput">
var fileInput = document.getElementById("myfileinput");

// files is a FileList object (simliar to NodeList)
var files = fileInput.files;

for (var i = 0; i < files.length; i++) {
  alert(files[i].name + " has a last modified date of " + files[i].lastModifiedDate);
}

Reduced time precision

To offer protection against timing attacks and fingerprinting, the precision of someFile.lastModifiedDate.getTime() 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
someFile.lastModifiedDate.getTime();
// 1519211809934
// 1519211810362
// 1519211811670
// ...


// reduced time precision with `privacy.resistFingerprinting` enabled
someFile.lastModifiedDate.getTime();
// 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.

Specifications

Though present in early draft of the File API spec, this property has been removed from it and is now non-standard. Use File.lastModified instead.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`lastModifiedDate` Deprecated'Non-standard'	Chrome Full support 13	Edge Full support 12	Firefox No support 15 — 61	IE Full support 10	Opera Full support 16	Safari No support No	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android No support No	Opera Android No support No	Safari iOS No support No	Samsung Internet Android Full support Yes

Legend

Full support: Full support
No support: No support
Non-standard. Expect poor cross-browser support.': Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.': Deprecated. Not for use in new websites.