XOR Cipher Tool
Free online XOR cipher tool. Encrypt or decrypt text with a key using the XOR cipher and get hex output. Supports UTF-8 and hex keys. 100% client-side, no data sent to servers.
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What is XOR Cipher Tool?
The XOR cipher is one of the simplest symmetric encryption schemes: every byte of the message is combined with a key byte using the bitwise exclusive-or (XOR) operation. Applying the same key a second time reverses the process, so the same key both encrypts and decrypts. This tool runs entirely in your browser — your text and key never leave your device.
Key Benefits
- Understand how XOR-based symmetric encryption works byte by byte
- Choose UTF-8 or hex keys and get clean hex ciphertext output
- Round-trip verification with a one-click swap-and-decrypt
- No sign-up, no network, no tracking — fully offline and private
Common Use Cases
- •Students learning the fundamentals of symmetric cryptography
- •CTF participants decoding repeating-key XOR challenges
- •Developers verifying byte-level encoders and decoders
- •Quickly obfuscating non-sensitive strings for config or puzzles
- •QA engineers testing how systems handle arbitrary byte streams
How to Use the XOR Cipher Tool
- Pick a Mode: Choose Encrypt to turn text into hex ciphertext, or Decrypt to convert hex ciphertext back into readable text. Both operations use the same XOR key.
- Enter Your Key: Type your secret key as UTF-8 text (e.g. "secret") or switch the key format to Hex and enter raw bytes (e.g. 1a2b3c4d). The key is applied cyclically to each input byte.
- Paste Your Input: For encryption, type or paste the text you want to scramble. For decryption, paste the hex string you received from a previous encryption.
- Copy or Swap: The result appears instantly in the output box. Click Copy to save it, or Swap to move the result into the input and flip the mode for a round-trip check.
Key Features
- Symmetric encrypt and decrypt with a single shared key
- Accepts keys as UTF-8 text or raw hex bytes
- Ciphertext output as clean hex, decrypt input also from hex
- Cyclic key reuse handles keys shorter than the message
- Live stats: input byte length, key byte length, and key in hex
- Swap button flips encrypted output back into decrypt input instantly