Cryptography CTF Generator

39 Ciphers 6 Types Client-Side

Enter a flag, pick a difficulty and challenge type, then hit Generate. The engine builds a random cipher pipeline, encodes your flag, and outputs ciphertext with a full solution bundle including decryption keys and progressive hints.

Configure Challenge
Dynamic Composition (more variety)

No challenge yet

Configure your settings and click Generate.

Solution will appear here

Generate a challenge first.

Hints will appear here

Generate a challenge to see progressive hints.

Raw JSON will appear here

Complete challenge bundle in JSON format.

Frequently Asked Questions

Enter your flag, choose a difficulty level and challenge type, then click Generate. The engine picks a random pipeline of encoding and cipher steps, applies them to your flag, and produces ciphertext. You get a downloadable challenge plus a JSON bundle with the complete solution, decryption keys, and progressive hints.
Standard (single cipher pipeline producing ciphertext), Multi-Part (flag split into N parts each encoded differently), Crib Drag (two messages XOR'd with the same key), Hash Crack (SHA-256 hash plus wordlist), Cipher Identify (multiple-choice: name the cipher from its output), and Key Reuse (same Vigenere/XOR key on two messages for known-plaintext attack).
Yes, 100% free with no signup required. All encoding, encryption, and challenge generation runs entirely in your browser using JavaScript and the Web Crypto API. No data is ever uploaded to a server. You can use it offline once the page loads.
39 steps including: Base64, Base32, Hex, ASCII85, Morse, Binary, Octal, Decimal, A1Z26, NATO, Phone Keypad, Tap Code, URL Encode, ROT13, ROT47, Atbash, Caesar, Vigenere, Beaufort, Autokey, Affine, Rail Fence, Bacon, Polybius, Columnar Transposition, Substitution, Playfair, Bifid, Hill Cipher, ADFGVX, Nihilist, XOR, OTP, RC4, AES Encrypt, RSA Textbook, Compress, Decoy, and Reverse.
Instead of fixed templates, the dynamic composer randomly combines compatible cipher and encoding steps at generation time. It categorizes steps into groups (classical, modern, grid ciphers, encodings) and builds valid chains, giving hundreds of unique combinations per difficulty level.
The engine generates 3-7 hints based on the pipeline. Each hint reveals progressively more about the encoding chain. Hints are included in the JSON bundle and can be shared with solvers one at a time.

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