Character Frequency Counter Text
Count how often each character appears — handy for puzzles and ciphers.
Character Frequency Counter is a free online tool that count how often each character appears — handy for puzzles and ciphers. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.
- Price
- Free — no account, no quota, no watermark
- Category
- Text
- Where it runs
- In your browser, on your device
- Files uploaded
- None
- Technology
- plain JavaScript
- Settings
- 2
- Works offline
- Yes, after the first visit
About Character Frequency Counter
Every character is counted and ranked, which is the practical entry point to frequency analysis — the technique that breaks every substitution cipher. English letter frequency is remarkably stable across texts: E is about 12.7%, followed by T, A, O, I and N. A ciphertext whose most common letter appears near 12% is almost certainly a simple substitution.
How to use it
- Paste the text you want to run through character frequency counter.
- Set letters only and ignore case.
The 2 settings
| Setting | What it does | Default |
|---|---|---|
| Letters only | On or off. On by default. | On |
| Ignore case | On or off. On by default. | On |
Under the hood
| Runs on | plain JavaScript — runs the whole thing |
| Controls | Letters only, Ignore case |
Questions
How do I use this to break a cipher?
Compare the ranking to English frequencies. The most common ciphertext letter is likely E, the next T. For a Caesar cipher that single mapping gives you the shift outright.
Are spaces and punctuation counted?
They are counted and shown separately, since space is the most frequent character in ordinary English text and would otherwise dominate the ranking.