Analyze letter frequency online and see how often each alphabet letter appears in your text. The visual heatmap, letter counter, and comparison table reveal dominant, rare, and missing letters, helping you inspect ciphertexts, study writing patterns, check pangrams, and compare real text against expected language frequencies.
The quick brown fox jumps over the lazy dog
A compact pangram that contains every English letter at least once. Use it to confirm that the heatmap can show a full alphabet even in a short sentence.
KHOOR ZRUOG
HELLO WORLD shifted by 3. The most visible letters are not the usual English leaders, which makes the Caesar shift easier to notice.
To be or not to be that is the question
A short natural-language phrase with repeated common letters. Notice how T, O, E, and H stand out even before the sample becomes very long.
ATTACK AT DAWN ATTACK AT DUSK
A compact phrase with repeated words and letters. The heatmap makes A, T, and K stand out, which is useful for spotting repetition in ciphertext-like text.
Letter frequency shows how often each letter of an alphabet appears in a text, usually as a percentage of all counted letters. Natural languages are not random: English strongly favors letters such as E, T, A, and O, while Q, X, and Z are usually rare.
This online letter frequency analyzer works like a focused letter counter: it counts alphabet letters in your input, ignores spaces and punctuation for the letter totals, and displays the result as a color-coded alphabet heatmap. Darker cells indicate letters that appear more often, while pale cells reveal letters that are rare or missing entirely.
The sortable table adds exact counts and percentages, so you can move from a quick visual impression to a more precise comparison with the selected language profile. Use it for text statistics, alphabet frequency checks, pangram testing, writing analysis, and first-pass cipher inspection.
Letter frequency is one of the fastest first checks in classical cryptanalysis. A Caesar cipher shifts every letter by the same amount, so the most common ciphertext letter often points to the encrypted form of E or another high-frequency letter in the target language.
Simple substitution ciphers are harder, but their statistics still leak information. Each ciphertext symbol always represents the same plaintext letter, so the frequency pattern is distorted but not erased. Peaks, gaps, and repeated high-frequency letters can suggest likely substitutions before deeper analysis begins.
For a fuller cipher workflow, use this heatmap to spot obvious alphabet patterns first, then move to broader frequency analysis for words, bigrams, trigrams, and the Index of Coincidence. Short texts can be noisy, so treat the heatmap as a clue rather than a final answer. The longer the text, the more closely its distribution tends to resemble the reference language.
A letter frequency analyzer is useful whenever the shape of the alphabet matters. Writers and editors can check repeated letters or unusual distribution in sample text. Teachers can demonstrate why some letters are common and others are rare. Puzzle solvers can inspect substitution puzzles, cryptograms, and short ciphertexts before trying manual decryption.
It also works as a quick alphabet coverage tool. Paste a pangram, slogan, generated password phrase, or constrained writing sample to see which letters appear, which ones dominate, and which letters are missing. The heatmap gives the overview, while the table provides exact letter counts and percentages.
Analyze text frequencies and compare them with known language patterns for cryptanalysis.
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