Random Byte Generator

Random Byte Generator

Generate cryptographically secure random bytes in the format you need: hexadecimal, decimal, binary, octal or a single Base64 string. Random bytes are the raw material of salts, nonces, initialisation vectors, tokens and test payloads, and this tool gives you any amount up to 64 KiB with one click.

Output formats

• Hexadecimal – two digits per byte, optionally uppercase and with 0x.
• Decimal – values from 0 to 255, ready for Uint8Array or Python bytes([...]).
• Binary – eight bits per byte with optional 0b.
• Octal – three digits per byte, the notation used in C escape sequences.
• Base64 – all bytes encoded into one compact string for configs and HTTP headers.

The separator menu controls how bytes are joined: spaces by default, or commas for array literals, new lines for one byte per line, or nothing at all for a continuous hex string.

Typical uses

Developers generate 16 random bytes for an AES IV or a UUID-style identifier, 32 bytes for an HMAC key or a session secret, and longer sequences for fuzzing parsers, binary file formats and network protocols. Security learners use the output to see how salts change password hashes.

Secure by design

Bytes are produced with the Web Crypto API (crypto.getRandomValues) in your browser. Nothing is sent to a server and nothing is stored. Close the tab and the values are gone.

Need longer hexadecimal tokens instead of separate bytes? Use the Random Hex Generator. To turn your bytes back into text or files, see the Base64 Encode/Decode tool.