A syllable is a beat of sound in a word: “cat” has one, “banana” has three, “syllable” has three. Poets and songwriters count syllables because rhythm depends on them, teachers use them to teach reading, and the readability formulas behind scores such as Flesch rely on them.
Paste a word, a line or a whole text. The total number of syllables appears, along with the average per word and a table showing each different word and its syllable count.
How it counts, and where it slips
English spelling does not map neatly onto sound, so counting syllables by computer means working from rules of thumb. The approach here: very short words (three letters or fewer) count as one syllable; a trailing silent “e”, “es” or “ed” is ignored; and then each group of vowels counts as a syllable. That gets most everyday words right.
It is not perfect, and where it fails you should know why. Words where two vowels sit next to each other but are pronounced separately, such as “idea”, “poem”, “create” and “area”, are counted one short. So are words ending in a sounded “-ed”, like “wanted” and “needed”, because the ending is always dropped. Words with a silent syllable like “evening” (often said as two) or “every” (often said as two) are a matter of accent. Borrowed words, names and abbreviations may be off by one. Digits count as zero syllables, because “2026” is spoken as several words which depend on how you read it.
If your count really matters, such as for a competition haiku, use the tool as a first pass and say the line out loud while tapping your fingers to check any that look doubtful.
Haiku and the rest
The classic haiku pattern is three lines of five, seven and five syllables. Paste each line in turn and read the total. The same approach works for the limerick, with its roughly eight to nine syllables on the long lines, or for song lyrics, where lines should match their melody. Teachers can paste a spelling list to quickly sort words by length.
In English, syllable count and word length are only loosely connected. “Strengths” has nine letters and one syllable. “Aeon” has four letters and two. That is the reason for counting by sound and not by letter.
Where the numbers go next
The readability scores in the readability checker are built from the same counts, and the word counter gives you word and sentence totals. For a quick look at how a word is made up, the character counter breaks text into letters and other kinds of character, and the palindrome checker is a pleasant diversion if you enjoy word games.