Curifold Puzzle School · FREE PRACTICE SHEET
Solve a small code with a key
Decode a message using an explicit substitution key in the correct direction.
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Your puzzle
A fictional note says UHDG. The sender encoded each plain letter as the letter three places later in the alphabet, wrapping after Z. Recover the message using the supplied key instead of guessing a likely word.
- The coded message is UHDG.
- Encoding moves three alphabet positions forwards, wrapping after Z.
- Decode by reversing that replacement.
| Row | Letters |
|---|---|
| Plain | A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
| Coded | D E F G H I J K L M N O P Q R S T U V W X Y Z A B C |
Copy the coded message
Pair each coded letter with a plain letter
Write the decoded word
Re-encode every letter
Try another word and a wraparound
andrew-stinson.com/learn/puzzle-school/solve-a-small-code-with-a-key/ · 2026-10-06