Polybius Square
5 by 5 or 6 by 6 coordinate substitution cipher.
The Polybius Square replaces each plaintext letter with a pair of row and column symbols from an alphabet square. The traditional 5×5 grid uses 25 letters (I/J are commonly combined; the switch letter can be changed in Alphabet Options). The expanded 6×6 grid uses 36 characters and adds digits 0–9, so no letters need to be merged.
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Enter a keyword, phrase, or alphabet and the 5 by 5 square will be calculated for you.
This cipher only has 25 characters, so one character must be switched.
Case
Filter
Whitespace
Find & Replace
Quick insert:
Group
Every
chars