Classical cipher tools
Identify unknown text, encode or decode ten historical systems, and follow their relationships with private browser-based tools and complete worked examples.
Cipher family guide
- Start with an unknown sample
- The cipher identifier ranks format, alphabet, and statistical clues before sending the original input to a matching tool through a private URL fragment.
- Substitution and polyalphabetic ciphers
- Signals and coordinates
- Morse code represents characters with timed dots and dashes.
- Polybius square is the parent coordinate system
- Collon uses grid-edge letters and interleaves indicator series.
- Bifid separates Polybius coordinates and pairs an interleaved stream.
- ADFGVX expands the grid and adds keyed columnar transposition.
- Trifid extends Bifid into three dimensions; Nihilist adds numeric key values; Tap Code sends Polybius coordinates as knocks. Those Phase 2 tools are intentionally not published until Search Console data supports expansion.
Available cipher tools
🔎 Cipher identifierRank likely formats and classical ciphers from an unknown sample, with evidence and pre-filled decoder links.🏛️ Caesar cipher encoder and decoderShift letters by any value from 1 to 25, reverse the shift, or inspect every possible decoding.🔄 ROT13 encoder and decoderRotate every letter by 13 positions. Applying ROT13 twice restores the original text.🪞 Atbash cipher encoder and decoderReplace each letter with its mirror partner in the reversed alphabet. The same mapping decodes it.🔑 Vigenere cipher encoder and decoderApply a repeating keyword to shift each letter by a different amount, or reverse the shifts to decode.📡 Morse code translatorTranslate letters, digits, and common punctuation to international Morse, decode signals, or hear them at 600 Hz.▦ Polybius square cipherConvert letters to 5x5 row-column coordinates with an alphabetical or keyword-disordered square.🧩 Bifid cipher encoder and decoderInterleave Polybius row and column coordinates in adjustable periods to fractionate letter patterns.🎖️ ADFGVX cipher encoder and decoderFractionate letters and digits through a 6x6 grid, then apply a keyed columnar transposition.🧵 Collon cipher encoder and decoderUse letters from Polybius grid edges as coordinates, then interleave indicator rows in fixed-length series.