How are Finnish syllables counted?

Each syllable has exactly one nucleus. A nucleus is a single vowel, a long vowel written as a doubled vowel (aa, ää), or one of the permitted diphthongs. The number of nuclei in a word equals its syllable count.

What counts as a diphthong in Finnish?

Finnish permits diphthongs ending in i (ai, ei, oi, ui, yi, äi, öi), diphthongs ending in u or y (au, eu, iu, ou, äy, ey, iy, öy), and the three opening diphthongs ie, uo and yö. Each of these is a single syllable.

Why are three vowels in a row split?

Finnish has no triphthongs, so a run of three or more vowels never forms one syllable. The tool groups long vowels and diphthongs first, then treats any leftover vowel as its own syllable, which is the standard hiatus rule.

Does a doubled vowel add a syllable?

No. A doubled vowel such as aa or ää is a single long vowel and therefore one syllable, so maa has one syllable and hyvää ends in a single long-vowel syllable.

Is my text sent anywhere?

No. The vowel, long-vowel and diphthong rules are bundled into the page and run entirely in your browser, so your text stays on your device.

Finnish Syllable Counter

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The Finnish Syllable Counter counts syllables the way Finnish phonology defines them: by counting vowel nuclei. Finnish is unusually regular here — every syllable has exactly one nucleus, and that nucleus is a single vowel, a long vowel, or a permitted diphthong.

How it works

For each word the tool scans left to right and groups consecutive vowels into nuclei using three rules, in order:

Long vowel. A doubled vowel (aa, ee, ii, oo, uu, yy, ää, öö) is one long-vowel nucleus, so maa is one syllable.
Diphthong. Two different vowels that form a permitted glide count as one nucleus. Finnish allows the i-final set (ai ei oi ui yi äi öi), the u/y-final set (au eu iu ou äy ey iy öy), and the three opening diphthongs (ie uo yö).
Hiatus. Any vowel that is not part of a long vowel or diphthong starts its own syllable. This is how a run of three vowels gets split, since Finnish has no triphthongs.

The syllable count for the word is the number of nuclei found this way; consonants only mark syllable boundaries, never nuclei.

Worked examples

kah-vi → 2 syllables (a, i)
työ → 1 syllable (the diphthong yö)
ka-u-pun-ki would be wrong; the real split is kau-pun-ki → 3 syllables, because au is a diphthong
hy-vää → 2 syllables (y, then the long vowel ää)

Notes

The counter treats Finnish vowels a e i o u y ä ö as nuclei and everything else as consonants. It analyses each word independently, so it works on full sentences as well as single words.