Vowel/Consonant Counter

Counts vowels and consonants in a text input, with separate totals per letter and overall. By default, vowels are A, E, I, O, U; Y is configurable as either vowel, consonant, or context-dependent. Output also reports total letters, total characters, and ratio of vowels to consonants.

English text typically runs 38–42% vowels by letter count. Significant deviation (under 30% or over 50%) suggests non-English text, deliberate constraint (lipogram), or short sample size noise.

The English vowel ratio is a property of phonotactics — the rules governing which sound combinations are allowed in a language. English permits some consonant clusters (str-, -nths, -lpt-) but generally requires vowels between most consonants for syllable formation. The 38–42% baseline is empirically stable across genre and register: technical writing, fiction, news, and casual conversation all fall within this range when sample sizes exceed a few hundred letters.

Other languages diverge predictably. Hawaiian, with its CV syllable structure (consonant + vowel only), runs above 50% vowels. Czech and Polish, with extensive consonant clusters, run below 35%. Hungarian and Finnish hover near English. The vowel ratio is therefore a rough language-detection signal: a sample with 25% vowels is unlikely to be English, more likely Slavic or a language with heavy consonant clustering.

A worked example. Input: "The quick brown fox jumps over the lazy dog." Counting (Y as consonant): vowels e, e, u, i, o, o, u, o, e, e, a, o = 12. Consonants: 24. Total letters: 36. Vowel ratio: 33.3%. The pangram is intentionally varied, including all 26 letters at least once, which suppresses the typical English vowel ratio slightly. Longer ordinary text would reach the 40% baseline.

Lipograms (texts deliberately omitting a letter) produce diagnostic vowel counts. Ernest Vincent Wright's 1939 novel "Gadsby" contains no E. Vowel counts on Gadsby show E at 0% and other vowels disproportionately represented to compensate. Georges Perec's "La Disparition" (1969) avoids E in French. Detecting lipograms automatically is straightforward when the omitted letter is a common one; the absence of E in any sufficient English sample is a strong constraint signal.

Y handling deserves a separate note. Y functions as a vowel in syllabic position (sky, rhythm, gym, where Y carries the syllable nucleus) and as a consonant at the start of a syllable (yes, yellow, you). Linguistically, this is well-defined; algorithmically, it requires syllable detection or word-by-word lookup. The simple rule of treating Y as always-vowel or always-consonant approximates real usage well enough for casual analysis, with always-vowel slightly closer to the linguistic truth.

Limitations: the counter handles Latin alphabet text only. Other scripts (Cyrillic, Greek, Arabic, CJK) require their own analysis. Diacritic handling normalizes accented vowels (é, à, ü) to their base form for counting; in languages where diacritics distinguish phonemes (Hungarian, Vietnamese, Polish), this normalization is incorrect and the counts should be treated as approximate.