Array.prototype.find()
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2015.
Thefind() method ofArray instances returns the first element in the provided array that satisfies the provided testing function.If no values satisfy the testing function,undefined is returned.
- If you need theindex of the found element in the array, use
findIndex(). - If you need to find theindex of a value, use
indexOf().(It's similar tofindIndex(), but checks each element for equality with the value instead of using a testing function.) - If you need to find if a valueexists in an array, use
includes().Again, it checks each element for equality with the value instead of using a testing function. - If you need to find if any element satisfies the provided testing function, use
some(). - If you need to find all elements that satisfy the provided testing function, use
filter().
Try it
const array = [5, 12, 8, 130, 44];const found = array.find((element) => element > 10);console.log(found);// Expected output: 12Syntax
find(callbackFn)find(callbackFn, thisArg)Parameters
callbackFnA function to execute for each element in the array. It should return atruthy value to indicate a matching element has been found, and afalsy value otherwise. The function is called with the following arguments:
thisArgOptionalA value to use as
thiswhen executingcallbackFn. Seeiterative methods.
Return value
The first element in the array that satisfies the provided testing function.Otherwise,undefined is returned.
Description
Thefind() method is aniterative method. It calls a providedcallbackFn function once for each element in an array in ascending-index order, untilcallbackFn returns atruthy value.find() then returns that element and stops iterating through the array. IfcallbackFn never returns a truthy value,find() returnsundefined. Read theiterative methods section for more information about how these methods work in general.
callbackFn is invoked forevery index of the array, not just those with assigned values. Empty slots insparse arrays behave the same asundefined.
Thefind() method isgeneric. It only expects thethis value to have alength property and integer-keyed properties.
Examples
Find an object in an array by one of its properties
const inventory = [ { name: "apples", quantity: 2 }, { name: "bananas", quantity: 0 }, { name: "cherries", quantity: 5 },];function isCherries(fruit) { return fruit.name === "cherries";}console.log(inventory.find(isCherries));// { name: 'cherries', quantity: 5 }Using arrow function and destructuring
const inventory = [ { name: "apples", quantity: 2 }, { name: "bananas", quantity: 0 }, { name: "cherries", quantity: 5 },];const result = inventory.find(({ name }) => name === "cherries");console.log(result); // { name: 'cherries', quantity: 5 }Find the first prime number in an array
The following example returns the first element in the array that is a prime number, orundefined if there is no prime number.
function isPrime(n) { if (n < 2) { return false; } if (n % 2 === 0) { return n === 2; } for (let factor = 3; factor * factor <= n; factor += 2) { if (n % factor === 0) { return false; } } return true;}console.log([4, 6, 8, 12].find(isPrime)); // undefined, not foundconsole.log([4, 5, 8, 12].find(isPrime)); // 5Note:TheisPrime() implementation is for demonstration only. For a real-world application, you would want to use a heavily memoized algorithm such as theSieve of Eratosthenes to avoid repeated calculations.
Using the third argument of callbackFn
Thearray argument is useful if you want to access another element in the array, especially when you don't have an existing variable that refers to the array. The following example first usesfilter() to extract the positive values and then usesfind() to find the first element that is less than its neighbors.
const numbers = [3, -1, 1, 4, 1, 5, 9, 2, 6];const firstTrough = numbers .filter((num) => num > 0) .find((num, idx, arr) => { // Without the arr argument, there's no way to easily access the // intermediate array without saving it to a variable. if (idx > 0 && num >= arr[idx - 1]) return false; if (idx < arr.length - 1 && num >= arr[idx + 1]) return false; return true; });console.log(firstTrough); // 1Using find() on sparse arrays
Empty slots in sparse arraysare visited, and are treated the same asundefined.
// Declare array with no elements at indexes 2, 3, and 4const array = [0, 1, , , , 5, 6];// Shows all indexes, not just those with assigned valuesarray.find((value, index) => { console.log("Visited index", index, "with value", value); return false;});// Visited index 0 with value 0// Visited index 1 with value 1// Visited index 2 with value undefined// Visited index 3 with value undefined// Visited index 4 with value undefined// Visited index 5 with value 5// Visited index 6 with value 6// Shows all indexes, including deletedarray.find((value, index) => { // Delete element 5 on first iteration if (index === 0) { console.log("Deleting array[5] with value", array[5]); delete array[5]; } // Element 5 is still visited even though deleted console.log("Visited index", index, "with value", value); return false;});// Deleting array[5] with value 5// Visited index 0 with value 0// Visited index 1 with value 1// Visited index 2 with value undefined// Visited index 3 with value undefined// Visited index 4 with value undefined// Visited index 5 with value undefined// Visited index 6 with value 6Calling find() on non-array objects
Thefind() method reads thelength property ofthis and then accesses each property whose key is a nonnegative integer less thanlength.
const arrayLike = { length: 3, "-1": 0.1, // ignored by find() since -1 < 0 0: 2, 1: 7.3, 2: 4,};console.log(Array.prototype.find.call(arrayLike, (x) => !Number.isInteger(x)));// 7.3Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-array.prototype.find |
Browser compatibility
See also
- Polyfill of
Array.prototype.findincore-js - es-shims polyfill of
Array.prototype.find - Indexed collections guide
ArrayArray.prototype.findIndex()Array.prototype.findLast()Array.prototype.findLastIndex()Array.prototype.includes()Array.prototype.filter()Array.prototype.every()Array.prototype.some()TypedArray.prototype.find()