How the cryptogram solver works
In a cryptogram, also called a substitution cipher, each letter of a message is swapped for another letter, and the same swap is used all the way through. If G stands for O once, it stands for O everywhere.
The solver looks at the shape of every word, such as a three-letter word whose first and last letters match, and finds dictionary words with the same shape that fit together. It then fine-tunes the answer by checking how much the result reads like English, letter by letter. Most puzzles of a sentence or more are solved in a second or two.
Using hints and locked letters
If your puzzle comes with a clue, such as G = O, type it into the Clue box. You can also type any letter you are sure of into the key, under the letter it replaces, and it will be locked the next time you press Solve. This is the quickest fix when a name or an unusual word confuses the solver.
Press Reveal one letter to see a single letter at a time, starting with the most common letter in the puzzle, if you would rather solve it yourself with a little help. Practice puzzle makes a new cryptogram from a well-known saying so you can try one from scratch.
Solving cryptograms by hand
Start with one-letter words, which are almost always A or I. Common short words come next: three-letter words are often THE or AND, and a word ending in an apostrophe and one letter is usually followed by S or T. The most frequent letter in a long cryptogram is very often E.
Look at repeated letters inside words, too. A word with the pattern of LITTLE or PEOPLE narrows things down quickly. Short puzzles are harder because there is less to go on, so a clue letter makes a big difference.
Questions and answers
What is the difference between a cryptogram and a Caesar cipher?
A Caesar cipher shifts every letter by the same amount, so there are only 25 possible keys. A cryptogram can swap letters in any order, giving millions of possible keys, which is why it needs a solver that looks at word shapes.
Why is the answer slightly wrong?
Very short puzzles can have more than one sensible answer, and names or rare words may not be in our list. Lock the letters you are sure of in the key and press Solve again.
Can a letter stand for itself?
In most published cryptograms, no letter stands for itself. The solver does not rely on that rule, so it works either way.
Does the solver keep my puzzle?
No. It runs entirely in your browser.