About Kryptos & Jim Sanborn

The Sculpture

Kryptos is a sculptural installation at the headquarters of the Central Intelligence Agency in Langley, Virginia. Dedicated on November 3, 1990, it is the work of American artist Jim Sanborn, with cryptographic consultation from Ed Scheidt, retired Chairman of the CIA Cryptographic Center.

The sculpture is a large S-shaped copper screen, supported by a petrified tree and curving around a bubbling pool of water. Its left half carries four encrypted messages; its right half carries the alphabet chart used to encrypt K1 and K2, deliberately mirrored so that it reads only from behind the piece. The screen is the centerpiece of a two-part work. At the entrance to the New Headquarters Building, tilted slabs of red granite flank the walkway, with copper sheets carrying International Morse code laid between the stone layers, and a lodestone sits beside a compass rose. In the courtyard, across from the screen, a reflective pool lies between layered slabs of granite.

Three of the four messages were first solved in late 1992 by a small NSA team, a result the agency did not make public until 2000. CIA analyst David Stein solved them independently in 1998, classified at the time, and computer scientist Jim Gillogly did the same in 1999, the first to announce a solution publicly. The fourth has resisted every attempt to decipher it since.

Bar widths are the real character counts. K4 is 97 characters, second shortest after K1, and the only one whose plaintext has not been published. Its shortness is part of the difficulty: there is very little text to get statistical purchase on. The counts above are ciphertext letters, and they total 865. The screen also carries four question marks, which is why the text as a whole is usually quoted as 869 characters.

How the cipher works

Sanborn did not hide the chart. He carved it into the sculpture. The right-hand half of the copper screen is an alphabet chart of the kind published by the 16th-century French cryptographer Blaise de Vigenère, and the CIA’s own description of the piece says the artist used that chart, “in combination with matrix coding systems,” to encipher the first three messages. The chart is mirror-reversed, so it can only be read from behind the screen.

It works as a lookup table: plaintext letter along the top, key letter down the side, ciphertext letter where the two meet. The alphabet is not A to Z. It starts with KRYPTOS and then runs through the letters that keyword has not already used, which is why the top row of the chart below reads KRYPTOSABCDEFGHIJLMNQUVWXZ, and the row labelled A on the sculpture begins with the same sequence.

A note on names. Cryptanalysts file this particular arrangement under Quagmire III, a label from the American Cryptogram Association’s classification scheme. It is a useful term for searching the literature, and you will meet it everywhere in the K4 community, but it is the solvers’ word rather than the sculpture’s. Sanborn and the CIA both describe the piece in plainer terms, as a Vigenère chart, and this site follows them.

Jim Sanborn

Jim Sanborn is an American sculptor whose career spans five decades. His work explores the intersection of science, nature, and secrecy, from uranium-ore photographs to lodestone compass pieces to encrypted texts embedded in stone and copper. Kryptos is his most widely known work, but it represents one facet of a deeply considered artistic practice.

The CIA gives the sculpture’s theme as “intelligence gathering”, and says Sanborn chose to interpret it in terms of how information is accrued throughout the ages. The letters were cut by hand with jigsaws: by Sanborn’s own written account, the chart plates alone took eight months, twenty assistants, nine jigsaws and nine hundred blades. He wrote the plaintext himself, as enigmatic prose (K3 paraphrases Howard Carter’s account of opening Tutankhamun’s tomb). He had once thought of asking a well-known novelist to contribute, but came to see that the fewer people who knew the text, the better.

For 35 years, from the 1990 dedication until 2025, Sanborn kept K4’s secret himself. He fielded thousands of inquiries from amateur and professional cryptanalysts and released periodic clues to sustain interest, while revealing little about the method. That is the part of the achievement that is easiest to overlook and hardest to imitate. Designing a cipher is a season’s work; keeping one for three and a half decades, in public, under sustained and often ingenious pressure, is something else entirely.

In September 2025 the writers Jarett Kobek and Richard Byrne found scrambled strips of K4’s plaintext among Sanborn’s papers at the Smithsonian’s Archives of American Art. Sanborn confirmed them, said they had been included by mistake, and the files were sealed. On November 20, 2025 he sold his Kryptos archive, including the K4 solution and his coding charts; in June 2026 the buyer was revealed as Paradigm. As of September 2026 no verified K4 plaintext has been made public.

With thanks to Jim Sanborn

Kryptos is Jim Sanborn’s work, and everything on this site is downstream of it. He made something genuinely new: a work of art that is also a real cryptographic problem, built to outlast the people who came to look at it. It has held up for more than 35 years against some of the most capable cryptanalysts in the world, professional and amateur alike, and it is still beautiful to stand in front of.

He has also been remarkably generous. For decades he has answered letters and emails from strangers, sat for interviews, corrected the record when the record needed correcting, released clues when interest flagged, and treated a very large number of persistent people with patience and good humour. None of that was required of him. An artist would have been well within their rights to install the piece, say nothing further, and let the world make of it what it would. He did the opposite, and the whole community that has grown up around Kryptos exists because of that choice.

We are grateful for both the puzzle and the generosity. His own site is jimsanborn.net, and his broader body of work rewards the visit.

What This Site Is (and Isn’t)

kryptosbot.com is a public elimination database. It documents what has been tested, what has been ruled out within bounded assumptions, and which claims were later retired, so that the K4 community can focus its energy on genuinely open approaches rather than independently re-discovering dead ends.

This site does not claim to be close to solving K4. It has no access to private information and is not affiliated with Jim Sanborn, Ed Scheidt, the CIA, the Smithsonian Institution, or Paradigm Operations LP. Results published here come from the project’s own code, in its public codebase on GitHub. That public repository can lag behind this site, and some scripts read reference texts that are not published there, so not every result can yet be re-run from it alone.

Related Works by Sanborn

Antipodes (1997): A sister sculpture at the Hirshhorn Museum (Smithsonian) in Washington, D.C. Two curved copper scrolls attached to petrified wood. One repeats the Kryptos ciphertext in a different order (K3, K4, K1, K2, then partly repeated), with small differences in spacing, dots and letters, one of which corrects the K2 error that reads UNDERGRUUND on Kryptos; the other carries Cyrillic text. Community accounts report Sanborn saying there is one clue on Kryptos that is not on Antipodes; we have not found a primary source for the remark. Unlike Kryptos, it belongs to a public museum, so no security clearance is needed to see it when it is on view.

On Antipodes the K4 passage, beginning OBKRUOXOGHULBSOLIFBBWFLRVQQPRNGKSS, has the same 97 letters as K4 on Kryptos.

Cyrillic Projector (early 1990s): An installation at the University of North Carolina at Charlotte, which bought it in 1997. A bronze cylinder with Cyrillic text cut through its walls, enciphered with a Vigenère chart whose alphabet begins with ТЕНЬ (Russian for “shadow”); the repeating key is reported to be МЕДУЗА (“Medusa”). The decrypted text is in Russian: instructions on using psychological control to develop and keep sources of information, and part of a classified KGB memo about the dissident Andrei Sakharov. Solved in 2003 by Frank Corr and Mike Bales. Sanborn’s working charts for this piece (preserved at the Smithsonian) reveal a multi-step encoding process (letters to Morse code to binary numbers). We tested this same encoding process on K4 and it didn’t produce any matches, though it can’t be entirely ruled out as one layer of a more complex scheme.