Finnish phonology

Unless otherwise noted, statements in this article refer to Standard Finnish, which is based on the dialect spoken in the former Häme Province in central south Finland. Standard Finnish is used by professional speakers, such as reporters and news presenters on television.

Finnish makes phonemic contrasts between long and short vowels, even in unstressed syllables, though long mid vowels are more common in unstressed syllables. Each short monophthong has a long counterpart with no real difference in acoustic quality. Long vowels are phonemically perceived as two identical vowels in succession and vowel length is not a phonemic quality akin to vowel height.

The table below lists the conventionally recognized diphthongs in Finnish. In speech (i.e. phonetically speaking) a diphthong does not sound like a sequence of two different vowels; instead, the sound of the first vowel gradually glides into the sound of the second one with full vocalization lasting through the whole sound. That is to say, the two portions of the diphthong are not broken by a pause or stress pattern. In Finnish, diphthongs are considered phonemic units, contrasting with both long vowels and with short vowels. Phonologically, however, Finnish diphthongs usually are analyzed as sequences (this in contrast to languages like English, where the diphthongs are best analyzed as independent phonemes (see International Phonetic Alphabet for English.)

Diphthongs ending in i can occur in any syllable, but those ending in rounded vowels usually occur only in initial syllables, and rising diphthongs are confined to that syllable. It is usually taught that diphthongization occurs only with the combinations listed. However, there are recognized situations in which other vowel pairs diphthongize. For example, in rapid speech the word yläosa ('upper part', from ylä-, 'upper' + osa, 'part') can be pronounced [ˈylæo̯sɑ] (with an /æo/ diphthong). The proper pronunciation is [ˈylæ.ˌosɑ] (with those vowels belonging to separate syllables).

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