What is hexadecimal?

Hexadecimal represents each eight-bit byte with exactly two base-16 digits, 0-9 and a-f. This encoder operates on UTF-8 or uploaded bytes and emits lowercase pairs; the decoder removes whitespace and reads pairs back into bytes.

Why use hex?

Use hex to inspect byte streams, hashes, protocol fields, or file signatures because byte boundaries remain obvious. It doubles raw size, an odd number of digits is invalid, and it provides no compression, encryption, or integrity by itself.

Hex in Bash

# Encoding
printf 'Hello' | xxd -p
# Output: 48656c6c6f

# Decoding
printf '48656c6c6f' | xxd -r -p
# Output: Hello

Hex in JavaScript

// Encoding
let encoded = Buffer.from("Hello").toString("hex");
console.log(encoded);
// Output: 48656c6c6f

// Decoding
let decoded = Buffer.from("48656c6c6f", "hex").toString();
console.log(decoded);
// Output: Hello

Hex in Go

package main
import (
	"encoding/hex"
	"fmt"
)
func main() {
	// Encoding
	encoded := hex.EncodeToString([]byte("Hello"))
	fmt.Println(encoded)
	// Output: 48656c6c6f

	// Decoding
	decoded, _ := hex.DecodeString("48656c6c6f")
	fmt.Println(string(decoded))
	// Output: Hello
}

Hex in PHP

// Encoding
$encoded = bin2hex("Hello");
echo $encoded . "\n";
// Output: 48656c6c6f

// Decoding
$decoded = hex2bin("48656c6c6f");
echo $decoded . "\n";
// Output: Hello

Hex Encoder & Decoder

Decode Hex

About Hexadecimal