Character Frequency Counter
See exactly how often each character appears — with a visual bar chart.
What is character frequency analysis?
Character frequency analysis counts how many times each distinct character appears in a body of text. In English prose, the letter E is the most common (about 13% of characters), followed by T, A, O, I, and N. Frequency analysis was historically used to break simple substitution ciphers — if the most common character in an encrypted text is X, it likely represents E.
Frequently asked questions
What does “case sensitive” do?
When case sensitivity is off (the default), uppercase and lowercase letters are merged — A and a are counted as the same character. Turn it on if you want to distinguish them, for example when analysing code where casing is meaningful.
Why is whitespace excluded by default?
Spaces are almost always the most frequent character in prose and would dominate the chart, making it harder to compare letter frequencies. Enable “Include whitespace” if you specifically want to analyse spacing patterns.
Can I use this to analyse code?
Yes — paste any source code and you can see which symbols appear most. Enable case sensitivity for code analysis since variable names like myVar and MyVar are distinct identifiers.
