How the counter reads a line
The core method is vowel-group counting: the tool scans each word for groups of consecutive vowel letters (a, e, i, o, u, and sometimes y) and treats each group as one syllable, since English syllables are built around a vowel sound. The word 'music' has two vowel groups, u and i, giving two syllables, and 'calculator' has four, a, u, a, o, giving four syllables, which matches how both words are actually said.
Raw vowel-grouping alone gets a lot of English wrong, so the tool layers on the language's most common exceptions: a silent trailing e is dropped rather than counted, so 'like' and 'name' stay at one syllable instead of two; an -ed ending only adds a syllable when it follows a t or d sound, so 'wanted' is two syllables but 'walked' is one; and a short list of known irregular words, ones that break the vowel-group rule outright, are matched directly rather than counted mechanically.