ADFGX Cipher

Use a keyed ADFGX square followed by keyed columnar transposition.

Keys

ADFGX first maps letters into coordinate pairs labelled A D F G X, then scrambles that coordinate stream with a columnar transposition keyword.

Square keyword

Builds the 5x5 square. Duplicate letters are removed, and J is merged into I.

Transposition keyword

Columns are read in sorted key order. Duplicate key letters keep their original left-to-right order.

ADFGX square

Square key None

Column key None

Type: Fractionating transposition Square: 5 x 5 Labels: A D F G X I/J: Merged

Options

Group ciphertext output

Encryption removes spaces, punctuation, and digits before building the coordinate stream. Grouping only changes the displayed ciphertext.

Process details

Normalized plaintext

Fractionated stream before transposition

Column read order

Output stats

Mode: Encrypt Input chars: 0 Processed chars: 0 Coordinate chars: 0 Columns: 0 Rows: 0 Output chars: 0 Display groups: 0

Example: with square key CARGO and transposition key ZEBRAS, ATTACK AT ONCE encrypts to GFADG AGADD DXGAG AGDXF AAAF.

Input

Output

Using This Tool: Guide & Notes Show guide

ADFGX turns letters into coordinate pairs with a keyed 5x5 square, then applies columnar transposition.

How to use it

Set the square key to build the Polybius-style alphabet square.
Set the transposition key to control column order.
Paste alphabetic plaintext or ciphertext into the input box.
Use the same square and transposition keys when decrypting.

Options and settings

Square key changes the first substitution stage.
Transposition key changes the column readout stage.
Grouping makes the final ADFGX stream easier to copy.
I/J handling matters because the classic square has 25 cells.

Notes

ADFGX uses only the symbols A, D, F, G, and X in its coordinate stream.
Both stages matter. A correct square key with a wrong transposition key will not decrypt cleanly.

ADFGX and ADFGVX: Fracturing Letters for Wartime Radio

The World War I field ciphers that split characters into coordinates, scattered those coordinates across the page, and made intercepted radio traffic far harder to analyse at speed.

Read the article

Signal acquired

A note from the team

We build these tools because we love cryptography, encoding, and making difficult ideas easier to explore. If they've helped you, even a small coffee means the world to the project. Thank you!

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