Jefferson Cipher Decoder

Pick the wheels, type their order or a key phrase, paste the code, and read the row the page picks.

Jefferson Cipher Decoder

Code to decode: HQRZX HCTZB LFOQS JAYKH NBKZX

This is a sample. Type or paste your own code over it.

Message

ASPAREKEYISUNDERTHEKETTLE
All 25 rows

Every row of the cylinder, scored by how many common English letter pairs it has.

RowReadingScoreUse it
4 LikelyVXXGEDOUDYBOXMVERMDUXAJTL4.92
11 LikelyASPAREKEYISUNDERTHEKETTLE16.54In use
13 LikelyMYGPJSMBXOHEHLXVUDBAFVMNT4.11
1QFQWVUEHLWPLCRGZEVCYPCWPB0.00
2UWYMZBTMCHZYUPOSFUFOQDBYM0.00
3IOFIMNSYQZOJPTRUPOGFVEOBP2.83
5JCNTWZLVUDQTMNPHOLMTSSPJN1.04
6KTIBLAGFMNEAGOKTVTWDMZHUU2.72
7PNZUSIUJJRNQZHIFYKJVTXICY1.46
8WECNYKWDSUCZQGNOQJHELYAGG3.07
9DUSJCTQGFLMDJJBYWINRAWXQH3.12
10OGHQHXBIBXDPRFZMSFSWJNDHF1.35
12FKEYBOVCECAKKBJAZEPXBPGFZ0.65
14SIBFTPXAOPXSBEHNXCVZRQUMV0.00
15RHUKIMPNGGWBEKALGAOBKOSAI2.04
16YVJOPQJWRAIRIAWKKBIGGUNOO1.42
17NBMEOCYPHTUILCTBMSYPCRYWQ0.79
18GPODDRASKEFMDIQIBWLCYMREK3.41
19EAKHKGDXNMTCFWMQHRQJZKEVS0.69
20LMDSUVIRVVYVSYFGDXXNILQDD0.00
21BZACQLRLAKKHVXCWLQZQDHLRJ0.00
22XJLXNJFOPFRWWULCIPRIWJZSA0.73
23TLWLFWZZIQJGAZUPJNTSUGFIR1.04
24CRVVAFNKTSVNYVDDCZULHFVXC0.00
25ZDTRGYHQWJGXTSYXNGAMOICKW1.65
More options

Rows 1 to 25, one for each block. Leave it empty and the tool picks: the best-reading row to decode, a fresh row to encode.

  • 25 letters on 25 wheels: 1 block.
  • The key phrase gives the order 14 15 3 16 5 25 24 1 21 6 18 19 22 10 7 17 13 2 20 23 11 4 8 12 9.
  • Row 11 picked because it reads most like English. Check the other rows below if it looks wrong.
  • With the spaces back: a spare key is under the kettle
Each column is one wheel, turned so that row 0 spells the code. Row 15 is the message, which is row 11 counted backwards.
RowWheel 14Wheel 15Wheel 3Wheel 16Wheel 5Wheel 25Wheel 24Wheel 1Wheel 21Wheel 6Wheel 18Wheel 19Wheel 22Wheel 10Wheel 7Wheel 17Wheel 13Wheel 2Wheel 20Wheel 23Wheel 11Wheel 4Wheel 8Wheel 12Wheel 9
Row 0HQRZXHCTZBLFOQSJAYKHNBKZX
Row 1ZDTRGYHQWJGXTSYXNGAMOICKW
Row 2CRVVAFNKTSVNYVDDCZULHFVXC
Row 3TLWLFWZZIQJGAZUPJNTSUGFIR
Row 4XJLXNJFOPFRWWULCIPRIWJZSA
Row 5BZACQLRLAKKHVXCWLQZQDHLRJ
Row 6LMDSUVIRVVYVSYFGDXXNILQDD
Row 7EAKHKGDXNMTCFWMQHRQJZKEVS
Row 8GPODDRASKEFMDIQIBWLCYMREK
Row 9NBMEOCYPHTUILCTBMSYPCRYWQ
Row 10YVJOPQJWRAIRIAWKKBIGGUNOO
Row 11RHUKIMPNGGWBEKALGAOBKOSAI
Row 12SIBFTPXAOPXSBEHNXCVZRQUMV
Row 13MYGPJSMBXOHEHLXVUDBAFVMNT
Row 14FKEYBOVCECAKKBJAZEPXBPGFZ
Row 15ASPAREKEYISUNDERTHEKETTLE
Row 16OGHQHXBIBXDPRFZMSFSWJNDHF
Row 17DUSJCTQGFLMDJJBYWINRAWXQH
Row 18WECNYKWDSUCZQGNOQJHELYAGG
Row 19PNZUSIUJJRNQZHIFYKJVTXICY
Row 20KTIBLAGFMNEAGOKTVTWDMZHUU
Row 21JCNTWZLVUDQTMNPHOLMTSSPJN
Row 22VXXGEDOUDYBOXMVERMDUXAJTL
Row 23IOFIMNSYQZOJPTRUPOGFVEOBP
Row 24UWYMZBTMCHZYUPOSFUFOQDBYM
Row 25QFQWVUEHLWPLCRGZEVCYPCWPB
The working, step by step (1 row)

Each block is lined up on the wheels and read off its own row.

BlockCodeRowMessage
1HQRZXHCTZBLFOQSJAYKHNBKZX11ASPAREKEYISUNDERTHEKETTLE

Next step One wheel would do? Print a Caesar cipher wheelA key word and no wheels? Add it letter by letter

How it works

This Jefferson cipher decoder stacks lettered wheels in the order your key gives, sets the code on one row and prints the 25 others. One reads. Below are the 25 wheels of the M-94 and Wikipedia's ten example wheels.

Read the full guide

Wheels first, then the order

Under Wheels, choose the set your puzzle names: the US Army's 25 M-94 wheels or Wikipedia's ten. The page takes no others. Type the order, left to right, into Wheel order or key phrase. On the ten, 7 9 5 10 1 6 3 8 2 4 turns OMKEGWPDFN into retreat now in row 6.

When no row reads

If the picked row is wrong, open All 25 rows and press Use on a better one. A nearly right order gives itself away. With wheels three and four swapped, row 11 of the opening example says A SQORE KEY IS UNDER THE KETTLE. Longer M-94 messages went out in blocks of 25, each perhaps in a different row. Row for each block takes them.

Tips
  • No letter is sent as itself. If a guessed word puts E under E, slide it along.
  • M-94 wheels go by the letter after A, B 1 to Z 25. R 17 starts ARMY OF THE US.
  • Writing a clue? Name the wheel set and give a key phrase. Its letters, numbered alphabetically, set the wheel order.

Questions and answers

Does a Jefferson wheel cipher decoder work without the wheel order?

Not this one. It needs the wheel order, and it cannot try them all: ten wheels have 3,628,800 orders and the M-94's 25 more than 15 septillion. A guessed word is the way in, but that is work by hand.

Where are Jefferson's own wheels?

Nowhere, it seems. He described a stack of 36 or more in a 1790s manuscript and apparently never had it made. He dropped it in 1803, when Robert Patterson sent him a columnar transposition. The M-94 wheels here come from a device that was built.

Has the Jefferson cipher been broken?

Yes. Étienne Bazeries reinvented the cylinder in 1891 and is said to have thought it indecipherable. Gaëtan de Viaris solved it in 1893. The weakness: every wheel turns the same number of places between message and code. It belongs in a puzzle.

More tools

Browse Text styles

All 35 wheels

The 25 wheels of the US Army's M-94 25

  • M-94 wheel B 1 Starts ABC before it scrambles, and spells NAB over the join, where the last letter meets the first. In the opening example it sits 8th from the left, under the E of the message.
  • M-94 wheel C 2 Keeps CDE and IJK in their usual order, more of the plain alphabet than any other wheel in the set. In the opening example it sits 18th from the left, under the H of the message.
  • M-94 wheel D 3 Spells LAD over the join. In the opening example it sits 3rd from the left, under the P of the message.
  • M-94 wheel E 4 After A come E, D, C and B: the first five letters of the alphabet, all at the front. In the opening example it sits 22nd from the left, under the T of the message.
  • M-94 wheel F 5 Spells PIT. In the opening example it sits 5th from the left, under the R of the message.
  • M-94 wheel G 6 Spells URN, and META over the join. In the opening example it sits 10th from the left, under the I of the message.
Show all 35 wheels (29 more)

The 25 wheels of the US Army's M-94, continued

  • M-94 wheel H 7 No word to check it by. E is the 5th letter, counting A as the first. In the opening example it sits 15th from the left, under the E of the message.
  • M-94 wheel I 8 Spells JOB and SUM. In the opening example it sits 23rd from the left, under the T of the message.
  • M-94 wheel J 9 Spells RAJ over the join. In the opening example it sits at the far right, under the E of the message.
  • M-94 wheel K 10 Spells CAKE over the join. In the opening example it sits 14th from the left, under the D of the message.
  • M-94 wheel L 11 Starts ALT, like the key on a keyboard. In the opening example it sits 21st from the left, under the E of the message.
  • M-94 wheel M 12 No word to check it by. E is the 24th letter, counting A as the first. In the opening example it sits 24th from the left, under the L of the message.
  • M-94 wheel N 13 No word to check it by. E is the last letter before the wheel comes round to A again. In the opening example it sits 17th from the left, under the T of the message.
  • M-94 wheel O 14 Spells LEG. In the opening example it sits at the far left, under the A of the message.
  • M-94 wheel P 15 Spells MAP over the join. In the opening example it sits 2nd from the left, under the S of the message.
  • M-94 wheel Q 16 Spells NUB. In the opening example it sits 4th from the left, under the A of the message.
  • M-94 wheel R 17 Starts ARMY OF THE US, the one wheel that was not scrambled from end to end. In the opening example it sits 16th from the left, under the R of the message.
  • M-94 wheel S 18 No word to check it by. E is the 7th letter, counting A as the first. In the opening example it sits 11th from the left, under the S of the message.
  • M-94 wheel T 19 No word to check it by. E is the 20th letter, counting A as the first. In the opening example it sits 12th from the left, under the U of the message.
  • M-94 wheel U 20 No word to check it by. E is the 15th letter, counting A as the first. In the opening example it sits 19th from the left, under the E of the message.
  • M-94 wheel V 21 Spells MUD and TIP. In the opening example it sits 9th from the left, under the Y of the message.
  • M-94 wheel W 22 Spells LIE and COT, and YAW over the join. In the opening example it sits 13th from the left, under the N of the message.
  • M-94 wheel X 23 Spells REV. In the opening example it sits 20th from the left, under the K of the message.
  • M-94 wheel Y 24 Spells LOST and TECH, and FRIDAY over the join. In the opening example it sits 7th from the left, under the K of the message.
  • M-94 wheel Z 25 No word to check it by. E is the 22nd letter, counting A as the first. In the opening example it sits 6th from the left, under the E of the message.

The ten wheels of Wikipedia's example 10

  • Wikipedia wheel 1 Spells WAX, and FEZ over the join. It sits 5th from the left in Wikipedia's key, where it carries the E of retreat now.
  • Wikipedia wheel 10 Spells BOW and ELM. It sits 4th from the left in Wikipedia's key, where it carries the R of retreat now.
  • Wikipedia wheel 2 No word to check it by. E is the 4th letter of the line as Wikipedia lists it. It sits 9th from the left in Wikipedia's key, where it carries the O of retreat now.
  • Wikipedia wheel 3 Ends in LOCK. It sits 7th from the left in Wikipedia's key, where it carries the T of retreat now.
  • Wikipedia wheel 4 No word to check it by. E is the 14th letter of the line as Wikipedia lists it. It sits at the far right in Wikipedia's key, where it carries the W of retreat now.
  • Wikipedia wheel 5 Spells LAB and ends WXY. It sits 3rd from the left in Wikipedia's key, where it carries the T of retreat now.
  • Wikipedia wheel 6 Spells VET and keeps GHI in order. It sits 6th from the left in Wikipedia's key, where it carries the A of retreat now.
  • Wikipedia wheel 7 Spells SPY. It sits at the far left in Wikipedia's key, where it carries the R of retreat now.
  • Wikipedia wheel 8 No word to check it by. E is the 17th letter of the line as Wikipedia lists it. It sits 8th from the left in Wikipedia's key, where it carries the N of retreat now.
  • Wikipedia wheel 9 Spells HEN. It sits 2nd from the left in Wikipedia's key, where it carries the E of retreat now.

How this list was compiled: The 25 M-94 wheel alphabets were copied on 2026-09-19 from the wheel identification matrix at https://www.jproc.ca/crypto/m94.html, which that page credits to George Mace, and compared letter by letter with the list at https://www.cryptomuseum.com/crypto/usa/m94/index.htm. The two agree on 23 wheels. On wheels F 5 and Z 25 the second list prints one letter twice (U and K) and leaves out another (Y and H); a wheel carries each letter once, so the first list stands. The naming from B 1 to Z 25 by the letter after A, wheel 17 starting ARMY OF THE US, the count of 25 wheels and the way the device was used were checked against https://en.wikipedia.org/wiki/M-94_(cipher_machine), and the build script asserts the first two on every wheel. The ten example wheels, their order 7 9 5 10 1 6 3 8 2 4 and the code OMKEGWPDFN for retreat now come from https://en.wikipedia.org/wiki/Jefferson_disk, read on 2026-09-19; the script reproduces that code before it writes this list. No wheel alphabets by Jefferson are included, because that article records that his device apparently was never made. Every other example message was written for this site, encoded by the script, decoded again by a separate routine and checked to match. The words noted on each wheel were found and confirmed by the same script. Licence: public domain for the 25 M-94 wheel alphabets: bare letter orders stamped on a piece of United States Army equipment, conceived by Colonel Parker Hitt and developed by Major Joseph Mauborgne in 1917, as https://en.wikipedia.org/wiki/M-94_(cipher_machine) records (read 2026-09-20); the ten example wheels are not own work: they are random letter orders quoted unchanged, with credit beside the wheels, from Wikipedia's article Jefferson disk (https://en.wikipedia.org/wiki/Jefferson_disk), whose text is CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/); notes, rules and the other worked examples are own work