The find() method returns a value in the typed array, if an element satisfies the provided testing function. Otherwise undefined is returned. TypedArray is one of the typed array types here.

See also the findIndex() method, which returns the index of a found element in the typed array instead of its value.


typedarray.find(callback[, thisArg])


Function to execute on each value in the typed array, taking three arguments:
The current element being processed in the typed array.
The index of the current element being processed in the typed array.
The array find was called upon.
Optional. Object to use as this when executing callback.

Return value

A value in the array if an element passes the test; otherwise, undefined.


The find method executes the callback function once for each element present in the typed array until it finds one where callback returns a true value. If such an element is found, find immediately returns the value of that element. Otherwise, find returns undefined. callback is invoked only for indexes of the typed array which have assigned values; it is not invoked for indexes which have been deleted or which have never been assigned values.

callback is invoked with three arguments: the value of the element, the index of the element, and the typed array object being traversed.

If a thisArg parameter is provided to find, it will be used as the this for each invocation of the callback. If it is not provided, then undefined is used.

find does not mutate the typed array on which it is called.

The range of elements processed by find is set before the first invocation of callback. Elements that are appended to the typed array after the call to find begins will not be visited by callback. If an existing, unvisited element of the typed array is changed by callback, its value passed to the visiting callback will be the value at the time that find visits that element's index; elements that are deleted are not visited.


Find a prime number in a typed array

The following example finds an element in the typed array that is a prime number (or returns undefined if there is no prime number).

function isPrime(element, index, array) {
  var start = 2;
  while (start <= Math.sqrt(element)) {
    if (element % start++ < 1) {
      return false;
  return element > 1;

var uint8 = new Uint8Array([4, 5, 8, 12]);
console.log(uint8.find(isPrime)); // 5


Browser compatibilityUpdate compatibility data on GitHub

Chrome Edge Firefox Internet Explorer Opera Safari
find 45 14 37 No 32 9.1
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
find 45 45 37 32 9.3 5.0
find 4.0.0

See also

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