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Spider Cipher

The Spider Cipher encodes text using a method inspired by classic bifid/polybius techniques and the concept of a spider web. Each letter is replaced by a pair of letters according to its position in a predefined grid.

Limitation is the alphabet does not contain letters: Q and W

Spider cipher

Spider cipher tool. Source: Zoubek

Encoding​

To encode a message, each letter is looked up in the spider web grid and replaced with its corresponding letter pair. When a letter has multiple possible pairs, they cycle through on each use.

  • A → BC / JX / DG
  • B → AC / FX / EH

Decoding​

To decode, the process is reversed:

  1. Split the encoded message into pairs of letters
  2. Look up each pair in the spider web grid
  3. Replace each pair with its corresponding original letter

Example​

Encoded: BE BH GP JK CZ | DT DF FV MO RU

Decoded: hello kenny

The decoder figures out which original letter each pair represents by consulting the spider web mapping!

Learn More​

Demo​

Demo

Encode Options
Decode Options