A tool for detecting repeated sequences in ciphertexts and estimating key lengths

Classic cryptography implementations 🏛🗝

ビジュアルで理解するプレイフェア暗号ツール

回転グリル暗号の仕組みをビジュアルに学べるツール

Classical Cryptography Decryption Tool Written Using Vue.js and Electron

ヴィジュネル暗号の暗号化・復号を実現するWebツールです。

Educational Bacon’s Cipher lab: encoding/decoding, steganographic embedding, and historical insights.

Interactive web tool to grasp the strip cipher’s structure: generate strips, set selection/placement, then encrypt and decrypt step-by-step.

Educational tool to generate self-decoding JavaScript snippets using classic ciphers (Caesar implemented).

Web-based simulator to encode and decode messages using historical book codes (page:line:word system). Experience how spies and diplomats once exchanged secrets through ordinary books.

分置式暗号（concealment cipher）を楽しく学べるチャレンジ型ツール。

各列の文字を組み合わて文字列を生成するツール。ヴィジュネル暗号の暗号解読の終盤でも使える。辞書照合による鍵キーワードの推測機能を持つ。

Linear algebra–based classical cipher (Hill cipher) with 2×2 / 3×3 keys. Encrypt/Decrypt mod 26, with modular inverse and key validation.

Educational web tool focused on classical ciphers only—explaining substitution (mapping) vs. transposition (shuffle) with clean visuals and a short quiz. Links out to hands-on tools; no encryption/decryption is implemented here.

Classical Cipher Identification & Visualization

🔐 A playful security education tool that translates classical ciphers and encodings into colorful emoji sequences. Features Caesar, Vigenère, Morse, Binary/Hex, and custom emoji maps.

スキュタレー暗号のWebツールです。

アフィン暗号（Affine Cipher）を学習・体験できるWebツールです

シーザー暗号を解読するシンプルなWebツールです。

Interactive web tool to learn and visualize the Beaufort cipher: key generation, encryption/decryption, and comparison with Vigenère.