How do you solve a cryptogram?

Count the letters. The commonest is very likely E, one-letter words are A or I, and apostrophe-S endings give away S. Then guess and check.

How many possible alphabets are there?

26 factorial, about 4 × 10²⁶ — far beyond trying them all, which is why frequency analysis is the route in.

Is a cryptogram secure?

No. Frequency analysis breaks it reliably. It is a puzzle, not encryption.

Cryptogram Puzzle Generator

Replaces every letter with a different one, using a single alphabet that stays consistent through the message — the classic cryptogram you find on a puzzle page. Frequency-analysis aids are built in, because counting letters is how these are actually solved.

Your message

Anything you type stays in your browser — it is never uploaded, and never put in the page address.

Cipher

Letter groups

0 keeps the words. 5 sets it in classic five-letter blocks.

Seed (optional)

A word that makes the same puzzle come back — useful for a worksheet.

Remove the spaces between words (much harder)

Your puzzle will appear here.

What this generator does

Uses a full 26-letter substitution alphabet rather than a fixed shift, which is what makes it a genuine puzzle: there are 26 factorial possible alphabets, so trying them all is impossible and frequency analysis is the only way in. The Caesar generator next door is the easier relative, breakable by trying 25 keys.

How to use this tool

Type your message.
Pick the substitution alphabet for a full cryptogram, or Atbash for an easier mirror cipher.
Set letter groups or remove spacing to raise the difficulty.
Press Make puzzle, then use the solving aids or reveal the answer.

Understanding the controls

Your message: Longer messages are easier to solve, not harder — frequency analysis needs enough letters to be reliable, so a two-word cryptogram can be tougher than a paragraph.
Cipher: Substitution draws a fresh random alphabet each time. Atbash mirrors the alphabet — A becomes Z, B becomes Y — which is fixed, its own inverse, and much easier once spotted.
Letter groups: Zero keeps word boundaries, which is how a newspaper cryptoquote is set and the main foothold for a solver. Five hides them completely.
Remove the spaces: Makes the puzzle substantially harder by removing word lengths and the one-letter-word clue that usually cracks it open.

Worked examples

Key space: 26 factorial is about 4 × 10²⁶ alphabets — far too many to try, unlike a Caesar shift's 25.
Atbash: A↔Z, B↔Y, and so on. Applying it twice returns the original, so it needs no key at all.
Frequency: In ordinary English E is commonest, then T, A, O, I, N — the aids show your puzzle's own counts to compare.

Common use cases

A puzzle page for a newsletter or school magazine
A maths or computing lesson on frequency analysis
A quiet activity that takes real thought rather than a few minutes
An escape-room or treasure-hunt clue that should take a while
Practice at the classic newspaper cryptoquote

How this generator works

A random alphabet is drawn in which no letter maps to itself, and each letter of the message is replaced by the one in the corresponding position. Rejecting alphabets with fixed points matters: a letter that encodes to itself hands a solver a free clue, and about a third of random shuffles contain at least one. Decoding inverts the mapping, so the reveal is exactly the text you typed.

Randomness and fairness

A fresh substitution alphabet is drawn from the browser's cryptographic randomness for each puzzle, rejecting any that leaves a letter mapped to itself. Atbash draws nothing at all — the mapping is fixed. A seed reproduces the same alphabet using a deterministic, non-cryptographic generator, which is fine here because the cipher itself offers no security whatever — reproducibility for a worksheet is the only property being bought.

For how randomness is produced across the whole site, see how Generate Random works.

Limitations and good to know

A substitution cipher is not secure. Frequency analysis breaks it reliably given enough text, which is precisely why it makes a good puzzle and a bad secret.
Very short messages can be unsolvable rather than merely hard, because there are not enough letters for frequency analysis to say anything. Aim for at least a sentence.
Only A–Z is substituted. Digits, punctuation and accented characters pass through unchanged, which can give away structure.
Atbash has no key, so anyone who recognises it can decode instantly. It is an easier option rather than a different level of the same puzzle.

Common mistakes

Using a very short message and expecting it to be solvable: Frequency analysis needs letters. A sentence or two is the minimum for a fair puzzle; three words is often just guesswork.
Confusing this with the Caesar cipher: A Caesar shift moves every letter the same distance. A substitution alphabet is arbitrary, which is why it cannot be broken by trying 25 keys.
Choosing Atbash for a hard puzzle: Atbash has no key and is recognised instantly by anyone who has seen it. Use the substitution alphabet when you want difficulty.

Practical tips

Start solving with the shortest words: a one-letter word is A or I, and a common three-letter word is usually THE.
Use a quotation rather than an invented sentence — solvers can lean on familiarity once a few letters fall.
Keep spacing on for a class puzzle and turn it off for a competition.

Privacy and your data

Your message and the alphabet used to encode it stay in your browser. Nothing is uploaded, nothing is stored between visits, and nothing is written into the page address. Analytics records only the puzzle's length. Since nothing here is secure, do not use it for anything you genuinely need to protect.

A recreational and educational puzzle tool. Classical substitution ciphers offer no security and must never be used to protect real information.

Frequently asked questions

How do you solve a cryptogram?: Count the letters. The commonest is very likely E, one-letter words are A or I, and apostrophe-S endings give away S. Then guess and check.
How many possible alphabets are there?: 26 factorial, about 4 × 10²⁶ — far beyond trying them all, which is why frequency analysis is the route in.
Is a cryptogram secure?: No. Frequency analysis breaks it reliably. It is a puzzle, not encryption.