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CrypTool-Online
CrypTool-Online (CTO for short) offers applications for testing, learning and discovering old and modern cryptography.
Highlights 7
AES Animation
Interactive animation of the AES algorithm
Corona Tracing
Demonstration of the cryptographic protocol DP-3T
Msieve Factorizer
Factorization of large numbers using a quadratic sieve
OpenSSL
Ported to the web browser with WebAssembly
Password Check
Another local password evaluation algorithm
Password Generator
Local generation of random passwords
Password Meter
Evaluates the strength of an entered password locally
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)
Codings 6
ASCII
Letters are replaced by numbers of the ASCII code
Bacon
Coding that encrypts and hides letters in sentences
Barcode
Characters are encoded by strokes of different thicknesses
Base64
Coding, which is based on a 64 number system
Huffman
Encodes characters with minimal long binary words
Morse Code
Encodes letters using dashes and dots
Cryptanalysis 7
Autocorrelation
Correlates text with shifted versions of itself
Distributed AES Analysis
Demo attacking AES with distributed computing
Graphical Frequency Analysis
N-gram analysis that works interactively and graphically
Neural Cipher Identifier
Identifies the cipher type, with only a short given ciphertext
Number Converter
Converts numbers to various other number systems
Tabular N-gram Analysis
Counts and visualizes the number of n-grams
Vigenère Analysis
Determines the length of the key of a Vigenère cipher
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