Uint8Array.fromHex()

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

The Uint8Array.fromHex() static method creates a new Uint8Array object from a hexadecimal string.

This method parses the string into a byte array. To convert the string into a single number, use the parseInt() function with radix set to 16 instead.

Syntax

Uint8Array.fromHex(string)

Parameters

string

A hexadecimal string encoding bytes to convert to a Uint8Array. The string must:

Have an even number of characters because two characters encode one byte.
Only contain characters in the hexadecimal alphabet, which includes 0–9 and A–F (case-insensitive).
Not contain whitespace (unlike Uint8Array.prototype.setFromBase64()).

Return value

A new Uint8Array object containing the decoded bytes from the hexadecimal string.

Exceptions

SyntaxError: Thrown if the input string contains characters outside the hex alphabet, or its length is odd.
TypeError: Thrown if the input string is not a string.

Examples

Decoding a hexadecimal string

This example decodes a hexadecimal string into a Uint8Array.

const hexString = "cafed00d";
const bytes = Uint8Array.fromHex(hexString);
console.log(bytes); // Uint8Array [ 202, 254, 208, 13 ]

Uppercase characters are also supported:

const hexString = "CAFEd00d";
const bytes = Uint8Array.fromHex(hexString);
console.log(bytes); // Uint8Array [ 202, 254, 208, 13 ]

Specifications

Specification
Uint8Array to/from base64 # sec-uint8array.fromhex

Browser compatibility

	Desktop					Mobile						Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	Deno	Node.js
`fromHex`	No	No	133	No	18.2	No	133	No	18.2	No	No	No	No