cipher.codes
Keyed Substitution
About
Keyed Substitution is a A monoalphabetic substitution cipher, where a keyword placed into beginning of the alphabet, and any duplicated letters are removed.
Supports
✅ Perfect Decoding
✅ Uppercase letters (A-Z)
✅ Lowercase letters (a-z)
❌ Numbers (0-9)
❌ Symbols (!@#$)
❌ Emojis (😍🤬👩🏾💻)
Numbers, Symbols, and Emojis
Numbers, symbols, and emoji are outputted as-is by this cipher.
What is “Perfect Decoding”?
Perfect Decoding is when the decoded text exactly matches the text that was encoded.
Source
View Keyed Substitution on Github
Method
Cipher Key
Given a key, create a new alphabet with that key in front.
For example, with a key of private you’ll see the cipher alphabet below, in comparison to the standard English alphabet.
key = 'private'
cipherAlphabet = privatebcdfghjklmnoqsuwxyz
standardAlphabet = abcdefghijklmnopqrstuvwxyz
Encoding
cipherAlpha.indexOf(letter)
Decoding
standardAlphabet.indexOf(letter)
Live Example
Variables
Based on the current settings for Keyed Substitution:
key = lorem
The computed cipher alphabet is:
loremabcdfghijknpqstuvwxyz
Sample String
Hello World!
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyz
0123456789
!@#$
✨🦄✨
When, Encoded
Cmhhk Wkqhe!
LOREMABCDFGHIJKNPQSTUVWXYZ
loremabcdfghijknpqstuvwxyz
0123456789
!@#$
✨🦄✨
Then, Decoded
Hello World!
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyz
0123456789
!@#$
✨🦄✨
