ADFGX Cipher
Encode or decode the two-stage ADFGX field cipher.
How ADFGX Cipher works
ADFGX Cipher handles a message in two stages: a keyed Polybius square outputs only A, D, F, G, and X, then a second keyword transposes those fractionated letters. The square key builds a 25-letter I/J alphabet; coordinate labels replace letters, and stable alphabetical column ordering applies or reverses the transposition. The ADFGX Cipher exposes its message, square keyword, transposition keyword, operation controls so this particular convention stays inspectable instead of hiding behind an unexplained preset.
ATTACKATONCE with square key CARGO and transposition key BATTLE produces DDDXAAAFGDXFGFADGAGAGAGA and decodes to the original normalized text. Historical-cipher students can isolate how substitution and transposition combine more effectively than either step used alone. The ADFGX Cipher presents a deterministic plain-text result that can be copied and compared with the worked value before it enters another workflow.
Limits and private processing
J merges with I, punctuation disappears, and repeated-key handling follows stable original order. ADFGX is historically important but cryptographically obsolete. The ADFGX Cipher performs its complete operation locally in your browser; neither the source text nor its settings are uploaded, stored remotely, or sent through an external request.
Frequently Asked Questions
How does the ADFGX Cipher work?
The square key builds a 25-letter I/J alphabet; coordinate labels replace letters, and stable alphabetical column ordering applies or reverses the transposition.
What does the default ADFGX Cipher example return?
ATTACKATONCE with square key CARGO and transposition key BATTLE produces DDDXAAAFGDXFGFADGAGAGAGA and decodes to the original normalized text.
What limitation should I know about?
J merges with I, punctuation disappears, and repeated-key handling follows stable original order. ADFGX is historically important but cryptographically obsolete.
Is the ADFGX Cipher private?
Yes. This specific adfgx cipher operation runs locally in your browser and does not transmit the input or settings.
Browse the full set of free, private, in-browser tools.