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CrypTool-Online

CrypTool-Online (CTO for short) offers applications for testing, learning and discovering old and modern cryptography.

Ciphers 26

ADFG(V)X
Cipher from WW1, which substitutes and transposes
AES (step-by-step)
The most common modern encryption method
Atbash
Simple monoalphabetic substitution cipher originally used on the Hebrew alphabet
Autokey
Variant of Vigenère, which also uses plaintext as key
Beaufort
Vigenère cipher, which uses reversed alphabet
Bit Shift
Shifts the characters of a text bit by bit
Caesar / Rot13
Shifting cipher, which was used by Julius Caesar
Enigma (step-by-step)
World War 2 rotor encryption machine
Gronsfeld
Variant of Vigenère using a number as its key
Hill
Polygraphic substitution, based on linear algebra
Kamasutra
Substitution cipher described in the Kama Sutra (400 BC)
Monoalphabetic Substitution
Cipher that replaces letters with letters/characters
Multiplicative
Simplified variant of the affine cipher
Porta
Vigenère cipher with half the key space
RSA (step-by-step)
The most widespread asymmetric method for encryption and signing
RSA visual and more
Didactic preparation of RSA
Rail fence
Transposition cipher that uses a railfence pattern
Redefence
Railfence cipher that reads lines in any order
Rotation
Cipher writes plaintext in blocks and rotates them
SHA256
Secure Hashing Algorithm - SHA256
Scytale
Cipher that writes messages on a belt
Simple Column Transposition
Cipher that interchanges lines of the plaintext
Trithemius
Precursor of the Vigenère tableau (with fixed key)
Vernam
Using XOR for implementing a one-time pad (OTP)
Vigenère
First strong polyalphabetic cipher
XOR
Single bits are XORed (typical component of more complex ciphers)
nothing found ¯\_(ツ)_/¯