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🕵️ SUBSTITUTION CIPHERS 🕵️

Substitution ciphers are where one character is replaced by another character.

Frequency & Word Analysis

Decryption helper website Decryption helper website from the lecture

Frequency analysis website

breaking substitution ciphers tips

  • Look for one/two letter words
  • Look for apostrophes
  • Look for repeating letters
  • Use the above website to analyse the frequency of words and compare against common letters

Decrypting Substitution Ciphers

task

Decrypt the following ciphers. Note that punctuation matters when inputting your answers. Upper and lower case does not matter.

The following all have different cipher keys.

Cipher 1

VJIF RPF GJPY XPFRE, VJIF RKDAFLF XPFREYFVV, RYH VJIF DRLF XPFREYFVV EDPUVE UNJY EDFI.

Cipher 2

HM'S V UZRRI MKHRW, VQCHMHJR. HM NVR MVPT JRT MJ SZCOHQT KTHWKMS JG KVGGJLHRW YTXMKS. VRY SJQTMHQTS MKTI VGT JRT VRY MKT SVQT.

Cipher 3

DST HTEIFL YEEC TEIC WNOCE WE'TE OK VNEF. OV'L DKCP WNEK WE WIBE WE TEICOLE VNOKML WETE LVTIKME.