Consonant Remover

Consonant removal is a character-level text transformation that strips every non-vowel letter from a string while preserving whitespace, digits, and punctuation. The operation maps an input alphabet of 26 Latin letters down to the vowel subset {a, e, i, o, u}. This tool extends coverage to accented variants (á, ë, ö, ü, etc.) totaling over 60 recognized vowel forms. Applications range from phonological analysis and linguistic pattern research to creative writing constraints and cipher construction. Misidentifying a character as consonant or vowel corrupts downstream analysis. This tool handles uppercase preservation, extended Latin diacritics, and non-Latin pass-through correctly.

Note: the classification treats y as a consonant by default, consistent with standard English orthographic convention. In languages where y functions as a vowel (Finnish, Welsh), enable the optional toggle. The tool processes text locally in the browser. No data is transmitted to any server.

The consonant removal function f operates on each character c of an input string S of length n:

where the per-character gate function g is defined as:

where V = {a, e, i, o, u, á, é, …} is the set of recognized vowel characters, L is the set of all Unicode letters (detected via regex /\p{L}/u), and ε is the empty string. Characters that are letters but not vowels (consonants) are deleted. All non-letter characters (digits, spaces, punctuation, symbols) pass through unchanged. When the optional toggle is active, y and Y are added to set V.