The MutationObserver method takeRecords() returns a list of all matching DOM changes that have been detected but not yet processed by the observer's callback function, leaving the mutation queue empty. The most common use case for this is to immediately fetch all pending mutation records immediately prior to disconnecting the observer, so that any pending mutations can be processed when stopping down the observer.


mutationRecords = mutationObserver.takeRecords()



Return value

An array MutationRecord objects, each describing one change applied to the portion of the document's DOM tree.

Note: The queue of mutations which have occurred but not been delivered to your callback is left empty after calling takeRecords().


In this example, we demonstrate how to handle any undelivered MutationRecords by calling takeRecords() just before disconnecting the observer.

var targetNode = document.querySelector("#someElement");
var observerOptions = {
  childList: true,
  attributes: true

var observer = new MutationObserver(callback);
observer.observe(targetNode, observerOptions);

/* ...later, when it's time to stop observing... */

/* handle any still-pending mutations */

var mutations = observer.takeRecords();

if (mutations) {


The code in lines 12-17 fetches any unprocessed mutation records and invokes the callback with that list of records so that they can be processed. This is done immediately prior to calling disconnect() to stop observing the DOM.


Browser compatibilityUpdate compatibility data on GitHub

Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 18 Yes 14 11 15 6
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support Yes 18 Yes 14 14 6 Yes

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