Free, client-side cryptography tools — your data never leaves your browser
All tools on this page run entirely in your browser. No data is sent to any server. You can even use these tools offline after the page has loaded.
Encrypt or decrypt text using the Caesar cipher. Shift each letter by a fixed number of positions.
Encrypt or decrypt using the Vigenere cipher with a keyword. Much stronger than Caesar for long messages.
Check how strong your password is. Analysis runs entirely in your browser — nothing is transmitted.
Compute cryptographic hashes using MD5, SHA-1, and SHA-256. All computation happens in your browser.
Convert text to Morse code or decode Morse code back to text. Separate Morse characters with spaces, words with " / ".
Encode text to Base64 or decode Base64 back to text. Note: Base64 is encoding, not encryption — it provides no security.
Encrypt or decrypt using the XOR cipher with a key. XOR is a fundamental operation in many modern encryption algorithms.
Encrypt or decrypt using the Rail Fence transposition cipher. Letters are written in a zigzag pattern across multiple rails.
Transform text using the Atbash cipher — the alphabet is reversed (A↔Z, B↔Y, etc.). Encryption and decryption are the same operation.
Apply ROT13 — a Caesar cipher with shift 13. Applying twice returns the original text. Commonly used to hide spoilers online.