CYPHERSOLVER

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Beinecke MS 408 · c.1420not solved

The Voynich manuscript

Statistical tests on the transliteration of Beinecke MS 408; no text was obtained. Plaintext and simple substitution, transposition or abjad renderings of eleven European languages are excluded. A verbose cipher of glyph groups and structured meaningless text remain, about even.

h2 2.2–2.9 bits against a 3.3 floor · slot grammar 1.7–2.3× more rigid than any language

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Vienna · 1644key from external plaintext · partial

Fra Giovanni di Lucca to Ferdinand III, 1644

A 231-figure Italian cipher paragraph in a friar’s letter to the Emperor (DECODE R2159), a substitution with two figures for each vowel. The key was recovered using the opening words Tomokiyo had published as a crib, and every figure was decrypted; checked against the manuscript, the apparent polyphony turned out to be ten misread 4s and three encipherment slips. The Grand Hetman Koniecpolski offers to keep the Turk from Rákóczi, raise Moldavia against him and give two thousand Cossacks.

“il principe di Bogdania, et li darò dumilia Cosachi … che non faccia pace fin che non l’habbi humiliato o vinto”

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United States · 1808key from external plaintext

Armstrong’s coded postscript to Madison, 1808

A 49-group postscript in the code THE=972. The code was recovered from a State Department clerk’s pencil decodes of Armstrong’s 1806 despatches on NARA microfilm, merged with Tomokiyo’s partial table from a known-plaintext letter, with remaining groups inferred from their alphabetical position. All 49 groups are decoded, the last with one digit emended: Armstrong wants Russel as consul at Paris, not the Irish-born Warden. With about 160 more values the same table then decoded twelve further despatches of 1807–1810, among them the warning of February 1808 that France offers alliance with one hand and menaces war with the other.

“Russel ought to be the consul: he is an American by birth … Next to him in fitness is O’Mealy, but he is, like Warden, an Irishman.”

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Swatow → Tokyo · 1916ciphertext-only break

The Swatow telegram to Sun Yat-sen, 1916

A telegram intercepted by the Japanese Foreign Ministry, in the Chinese telegraph code through a letter condenser. The condenser table was recovered from the ciphertext alone by testing every table of the systematic family known from Yamada’s condensers. 41 of about 44 characters are decoded; they report Mo Qingyu’s rising at Chaozhou.

潮城由莫擎宇獨立。我軍亦光復汕頭。後莫率大隊來，令我退出鎮守府…

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Pignerol → Suze · 1691key from external plaintext · partial

Feuquières to Catinat, Pignerol 1691

A 418-group despatch printed in figures in the 1819 Mémoires de Catinat, in the petit chiffre of the Pignerol governors. The code was recovered by aligning another letter in it, printed in the same edition with its contemporary translation, and carrying the values between the two letters; 586 of 601 groups have a value. The plan for the surprise of Veillane. Bazeries deciphered it in 1893 but did not publish the text.

“j’attaqueray [par] deux endrois, et surtout … prendray garde que les dragons ne puissent m’eschaper”

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Ireland / England · 1634–35key from adjacent plaintext · partial

Lord Maltravers to the Earl of Ormonde, 1634–35

Two letters printed by the HMC in 1895 with 59 figures of a numerical cipher and no decipherment. The key was recovered from the adjacent cleartext: a regular alphabet in blocks of three consecutive figures (consonants from 7, vowels from 64), nulls 91–111 and a small nomenclator. Seven of the nine code numbers were identified from Wentworth’s dispatches in Knowler’s Strafforde’s Letters (1739).

“he was angry [with the Lord Deputy] … upon his motion [Ormonde] is to be a councellor”

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Thirty favourites: the funny, the historic, the ingenious →

Latest findings

• 14 Nov 2026The Marquis of Mirabel to the Count of Gondomar, Paris, early 1622 — the one cipher letter of BNE MSS/18428 with no decipherment of the time, in the Lyon letter’s syllabary: Brice Dudout extended the key from the volume’s clears (one test failed, one partial) and read the letter in part, 182 of 250 cipher words sure write-up
• 13 Nov 2026Japanese Army Ministry cipher drafts on the Ryūkyū deployment, Feb–Mar 1879 — three drafts in the Army’s 1877 kana tables, each with the clerk’s plaintext beside the cipher: Brice Dudout transcribed them and identified tables 4, 1 and 6, and the Ministry’s kanji drafts of two of the messages settled the last open words (98 of 99) write-up
• 13 Nov 2026Steenackers to his Paris colleagues, pigeon telegram of 2 November 1870 — about two thirds of the inspectors’ code deciphered: it behaves as a paged alphabetical book, 238 values rebuilt from the clear words, 62% of groups valued as written The director of telegraphs at Tours sets out the line to take towards the post office, reports Prussians leaving Saint-Germain with pickaxes and gives a recipe for coating cotton balloons; names, about 30 words and seventeen digit slips stay open. write-up
• 13 Nov 2026Ormond to his son Arran, Dublin, 24 January 1677/8 — the twenty figures Ormond set as a trial of his son’s skill are S. Tomokiyo’s 1680 Ormond–Longford table with every number raised by 7 (found by Malcolm McBratney); read in part, 10 of 20 figures attested: “but it seems to Ormond not credible” write-up
• 13 Nov 2026Höpken and Carlson, Constantinople, 1741–1742: a Latin letter signed Ibrahim Effendi and the Khan of Crimea’s letter, added to the second code — the same four-digit key reads a bare Latin letter about the frontier islands in part (113 of 169 words, 40 on guesses) and agrees with the gloss of the Khan’s letter to the King of Sweden at 487 of 602 groups write-up

All 652 write-ups →