XOR Cipher — Encrypt, Decrypt & Single-Byte Brute Force
XOR text or hex against a repeating key, see the result as hex and printable text, and crack single-byte XOR with a brute-force ranker. Free, no upload.
Result appears here…
Result appears here…
Tries all 256 single-byte keys and ranks results by how printable they are — best guesses first.
🔒 XOR is a reversible obfuscation, not secure encryption — everything runs in your browser and nothing is uploaded.
What XOR cipher does
XOR (exclusive or) combines each byte of your input with a byte of the key. Type text or paste hex, enter a key as text or hex, and the tool shows the result in both hex and a printable-text view. Because XOR is symmetric, running the same key over the output again returns the original — so one tool both encrypts and decrypts.
Repeating-key XOR and single-byte brute force
Keys shorter than the data repeat cyclically, the classic repeating-key XOR. When a message was scrambled with a single-byte key, the brute-force button tries all 256 keys, scores each result by how printable it is, and lists the most likely plaintext first. Click a candidate to load its key and reveal the full decoded output.
Frequently asked questions
Is XOR secure encryption?
No. XOR with a short or repeating key is easily broken and is meant for obfuscation, CTF puzzles, and learning — not for protecting sensitive data. Use AES or a modern cipher for real encryption.
Can I use a hex key or a text key?
Both. Switch the key field between Text and Hex. A text key is UTF-8 encoded, while a hex key lets you supply exact bytes such as 2a or de ad be ef.
How does single-byte brute force work?
It XORs your input against every value from 0 to 255, ranks each result by its ratio of printable characters, and shows the top candidates so the correct key usually rises to the top for readable text.