# 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.

**URL:** https://convertto.tech/t/letter-frequency-analyser
**Category:** Text Tools (https://convertto.tech/c/text-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

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

## How to use

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

## FAQ

### 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.

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