Character & N-Gram Frequency Analyzer
Count the frequency of single characters, letter pairs (bigrams), triplets (trigrams), and longer n-grams in your text — overlapping, sliding-window counts sorted by how often each occurs, with percentages and a visual bar. A staple of substitution-cipher cryptanalysis and language identification (English's most common letters are E, T, A, O; its top bigrams are TH, HE, IN, ER). Runs locally in your browser.
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Frequency
An n-gram is a run of n consecutive characters; this tool counts every overlapping n-gram with a sliding window (so "aaaa" has three "aa" bigrams). With letters only on, everything except A–Z (and a–z) is stripped before counting, which is the usual setting for cipher and language analysis; turn it off to census every character including spaces. Case-insensitive lowercases first, so E and e merge. Percentages are of the total number of n-grams found. Pairs with the Word Frequency Counter (whole-word counts) and Statistics Calculator. Everything runs locally — nothing leaves your browser.