TypedArray.prototype.join()
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since September 2016.
The join() method of TypedArray instances creates and returns a new string by concatenating all of the elements in this typed array, separated by commas or a specified separator string. If the typed array has only one item, then that item will be returned without using the separator. This method has the same algorithm as Array.prototype.join().
Try it
const uint8 = new Uint8Array([10, 20, 30, 40, 50]);
console.log(uint8.join());
// Expected output: "10,20,30,40,50"
console.log(uint8.join(""));
// Expected output: "1020304050"
console.log(uint8.join("-"));
// Expected output: "10-20-30-40-50"
Syntax
join()
join(separator)
Parameters
separatorOptional-
A string to separate each pair of adjacent elements of the typed array. If omitted, the typed array elements are separated with a comma (",").
Return value
A string with all typed array elements joined. If array.length is 0, the empty string is returned.
Description
See Array.prototype.join() for more details. This method is not generic and can only be called on typed array instances.
Examples
Using join()
const uint8 = new Uint8Array([1, 2, 3]);
uint8.join(); // '1,2,3'
uint8.join(" / "); // '1 / 2 / 3'
uint8.join(""); // '123'
Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-%typedarray%.prototype.join |