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Letter Frequency Analyser

Count letter and character frequencies — useful for cryptograms and puzzle solving.

Letter frequency analysis counts how often each character appears and compares it to the standard distribution of written English, where E, T and A are most common. It is the classic first step in breaking a substitution cipher and a quick way to check whether text is a pangram.

Runs in your browser
Privacy
Runs entirely in your browser — nothing is uploaded
Cost
Free, unlimited, no sign-up

Frequently asked questions

What can letter frequency reveal?

Which language a text is in, whether it has been encrypted with a simple substitution, and whether it is natural writing at all. English peaks sharply at E and T; a flat distribution suggests random data or a strong cipher.

Why does frequency analysis break modern encryption?

It does not. Frequency analysis defeats substitution ciphers because each letter always maps to the same symbol. Modern ciphers produce output where every byte is equally likely regardless of the input, leaving nothing to count.

How to use the letter frequency analyser

  1. 1Enter or paste your text.
  2. 2Choose the count.
  3. 3The result appears immediately — copy or download it.

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