AES (128, 192, 256, 512)
128–512Advanced Encryption Standard (NIST FIPS 197). Supports 128, 192, 256 bits, and 512-bit cascade. GCM mode provides authenticated encryption (AEAD).
Online Cipher & Encryption — AES, ML-KEM, RSA, ECC & ChaCha20
Encrypt, decrypt, sign, and exchange keys directly in your browser. Supports NIST FIPS 203 (ML-KEM-512, 768, 1024), FIPS 204 (ML-DSA), hybrid RSA-OAEP, block ciphers, and elliptic curves with custom key import and download.
Symmetric passwords are cryptographically derived into exact key lengths using SHA-256 / PBKDF2.
Supported Cryptographic Algorithms
Explore modern authenticated ciphers, classical block constructions, and post-quantum lattice cryptography.
ChaCha20 (Stream)
256High-throughput stream cipher by Daniel J. Bernstein (RFC 8439). Standardized in TLS 1.3 and WireGuard VPN.
Twofish
128–256128-bit block cipher by Bruce Schneier, AES finalist with key-dependent S-boxes.
Blowfish
32–44864-bit Feistel cipher supporting variable keys up to 448 bits. The core of bcrypt password hashing.
Serpent
128–256AES finalist with 32 rounds of substitution-permutation network for extreme security margins.
Triple DES & DES
56 / 168Historic standards: DES (56-bit key) and Triple DES (3DES, three-stage EDE processing).
IDEA
128128-bit block cipher utilizing mixed algebraic groups. The foundation of original PGP.
RC4, RC5, RC6
40–2048Ron Rivest ciphers: stream cipher RC4, block cipher RC5, and AES finalist RC6.
Camellia & ARIA
128–256National cryptographic standards: Japanese Camellia (NTT/Mitsubishi) and South Korean ARIA (RFC 5794).
RSA & ECC (ECDSA/ECDH)
256–2048Public-key systems: hybrid RSA-OAEP 2048-bit encryption, ECDSA (P-256) digital signatures, and ECDH key agreement.
Diffie-Hellman Key Exchange
2048Classical Diffie-Hellman key exchange over discrete logarithm groups (RFC 3526 MODP 2048-bit).
ML-KEM (512, 768, 1024 FIPS 203)
Lattice KEMNIST FIPS 203 Post-Quantum standard (Kyber). Security levels: ML-KEM-512 (Level 1), ML-KEM-768 (Level 3), ML-KEM-1024 (Level 5) using Module-LWE lattices.
ML-DSA (Dilithium-65 FIPS 204)
Lattice SignNIST FIPS 204 Post-Quantum digital signature standard (Dilithium) based on module lattices.
Frequently Asked Questions
How does ML-KEM (Kyber) encryption work?
ML-KEM (FIPS 203) is a lattice-based key encapsulation mechanism. A hybrid scheme is used for text: the public key encapsulates an ephemeral secret, which is then used by AES-GCM to encrypt the message securely.
What is the difference between ML-KEM 512, 768, and 1024?
The number designates the lattice matrix rank. ML-KEM-512 targets AES-128 equivalent security, ML-KEM-768 matches AES-192 (the recommended default), and ML-KEM-1024 provides maximum post-quantum security matching AES-256.
Why is a hybrid scheme used for RSA?
Pure RSA-OAEP 2048 can only encrypt up to 190 bytes at a time. The hybrid scheme uses RSA to encrypt a 256-bit AES session key, which then encrypts messages of any length with AES-GCM.
How do I verify an ECDSA signature from an external source?
Enter the message in the input area, paste the hex signature in the 'Digital Signature' field, paste the author's public key in the 'Public Key' field, and click 'Verify Signature'.
Why does changing any character in the DES key produce garbage?
All passwords pass through a key derivation function (SHA-256/PBKDF2), ensuring that altering even a single character produces an entirely different key, causing decryption to fail.
How does key agreement work in ECDH and Diffie-Hellman?
You generate your keypair and paste your peer's public key in the 'Public Key' field. The algorithm derives the identical shared secret on both ends without transmitting it.
Can I save generated keys to files?
Yes, clicking 'Download Public' or 'Download Private' downloads your PEM or hex keys as files directly to your device.
Is it safe to paste private keys here?
Yes. All computations run 100% locally in your browser sandbox using Web Crypto API. No keys or plaintexts are ever sent over the network.
What is the avalanche effect in cryptography?
It is a crucial property where changing even one bit in the input plaintext or key changes approximately 50% of the output bits pseudo-randomly.
Related Developer Tools
All operations run locally in your browser.