Polybius Square Cipher Tool
Encode text into number pairs or decode number pairs back to text using the Polybius square cipher (5x5 grid).
Polybius Encoded
23 15 31 31 34
"HELLO" encoded as coordinate pairs
Letters Encoded
5.00
Grid Reference
1=ABCDE 2=FGHIK 3=LMNOP 4=QRSTU 5=VWXYZ
Note
I and J share position 24 in the standard grid