Algorithm Gallery

A simple direct substitution cipher where each letter is replaced by its number in the alphabet.

A World War I cipher that combines a Polybius square fractionation with columnar transposition.

A monoalphabetic substitution cipher where each letter is mapped to its numeric equivalent, encrypted using a simple mathematical function.

A substitution cipher where the alphabet is reversed.

A Vigenère-style cipher that uses the message itself as part of the key.

A method of steganography where each letter is replaced by a sequence of 5 characters, usually 'a' or 'b'.

Standard Base32 encoding and decoding.

Standard Base64 encoding and decoding.

Historical 5-bit character code telegraph encryption.

A substitution cipher similar to Vigenère, but using a slightly different mechanism that makes it its own inverse.

A cipher that combines the Polybius square with transposition to achieve fractionating.

Convert text to its 8-bit binary representation.

Shift alphabets by a set amount to encode messages.

A transposition cipher where the message is written in rows and read in columns defined by a keyword.

Convert text to its decimal (ASCII) representation.

A polyalphabetic substitution cipher that uses four 5x5 matrices to encrypt digrams.

A variation of the Vigenère cipher that uses digits instead of letters for the key.

Convert text to its hexadecimal representation.

A polyalphabetic substitution cipher based on linear algebra (2x2 matrix).

A substitution cipher that uses a keyword to reorder the alphabet.

Converts text to stylized 'l33tsp34k' using numbers.

Convert text to dots and dashes.

Converts text to NATO phonetic alphabet (Alpha, Bravo, etc.).

A more complex variation based on the Polybius square and an additive keyphrase.

Mathematically unbreakable cipher if the key is truly random and as long as the message.

Simple language game transformation.

The first literal digram substitution cipher, using a 5x5 matrix of characters.

A substitution cipher that represents each letter by its coordinates in a 5x5 grid.

A polyalphabetic substitution cipher that is its own inverse.

A transposition cipher that writes a message in a zigzag pattern across multiple rails.

Flips the entire message backwards.

Flipping each word in the text while keeping word order.

A simple rotation cipher that shifts letters by 1 (Caesar shift with offset 1).

A simple substitution cipher that replaces a letter with the 13th letter after it in the alphabet.

Combines ROT13 for letters and ROT5 for numbers.

Shifts all visible ASCII characters by 47 to scramble text.

A simple rotation cipher for numbers (0-9).

A polyalphabetic substitution cipher that uses a long passage of text as its key.

An ancient Greek transposition cipher using a rod with a fixed diameter.

A Caesar shift where the offset is derived from a text passkey.

A monoalphabetic substitution cipher using a keyed alphabet.

A substitution cipher that converts characters into digits with varying lengths.

Used by prisoners to communicate by tapping on bars or walls.

A 3D expansion of the Bifid cipher using a 3x3x3 cube to fractionate characters.

Standard percent-encoding for URI components.

A method of encrypting alphabetic text by using a series of interwoven Caesar ciphers.

A simple bitwise XOR operation between each character and a repeating key.