Category:Phonology
Feature:Vowel Quality Inventories WALS
Name:Small (2-4)
Languages (185):
Conlangs (165):
Miapimoquitch
Qþyn|gài
Jezzali
Yanusu
Skerre
Kisuna
Vilani
Lajik
Dahilese
Icnac
Waysignig
Ngeyunh hunting language
K'tle
Uscaniv
Kuyʔūn
Qichiuqtluq
Patakasama
All the vowels are :
a i u

a almost like in british pronunciation of car (X-SAMPA : between a: and A:)
i like in feel (X-SAMPA : i:)
u like in choose (X-SAMPA : u:)
Tama
Katkagor
Yulasa
Lhenazi

/a e i o/

Aveata
Nova
/a e i o/; < u > represents /w/, and may prove to have been a poor orthographic choice... Vowels contrast for tone and nasalization, and each diacritic codes tone and nasalization simultaneously (hence the profusion of vowel diacritics): /a_1 a~_1 a_2 a~_2 a_3 a~_3/ <á ā a ã à ą>
Rayalaka
Tanaman
Llapoyan
Wirid
Miirna

i, u, a

Sihaku
/i a u/
Dothraki
Apituka
Thiuas
Toilan
3 vowels. X-SAMPA: /i, u, A/. No phonemic diphthongs. [e] occurs as an allophone of /i/, [o] as an allophone of/u/, and [@] as an allophone of /A/.
Uzkian
Prakyũ (Classical)
Yaufulti
Rahwneʔ
Rarlang
Ukhshaya
Dapaq
Ataican
Jayus
Gnusyak [Ghnushak]
South Eresian
Insular Kett
Proto-Ksqrian
Proto-Aukkangtin
Tmaśareʔ
Llapakhi
/i  a  o /
/i: a: o:/
Fupoloypan
Trikuharric
i u a ɑ
Pateko
Slyrdian
/y u ɔ œ/
Qitatyattas

/a/,/i/,/u/, lengthened in stressed open syllables

Damin
Sarikan
Mithara
/i u ɛ ɑ/, with regressive harmony between /ɛ ɑ/
Mamambam
Vrlungla
Ulmiric
Qi (Irfikian Language)
Lántas
/i a u iː aː uː ai au iə uə m̩ n̩ ɻ̩ l̩/
Ebo Lingai
FKL
Atsn
Modern low Ponuhi
Pymmalian
Old Lonmai luna
Sonorian
Necarasso Cryssesa
/a e i o/
Dahawj
Black speech
ea-luna
Satang
/i/ /u/
  /a/
Proto-Zachydic
Apelcheq Maulochsab
Oligo

There is only ever 1 phonemic vowel, hence its phonetic value doesn't matter.

Wally Toxic
FeNeKeRe
Proto Tændean
Proto-Gramurn
Grru
LipTalk
Unrounded open back: a
Round close back: u
Unrounded close central: i
middle central (schwa): e
LCR
Tumbian
Nefer Jed
Ewheshenin
Primitive Ruminis
Minhast
Caryatic
Wihri
Traup
Doubleyew Eyepea
Salga
Spraka
Lwaitel
Jel
The consonant-vowel distinction is nowhere near as clear in Jel as it typically is, as everything but stops and clicks may be syllabic. The features involving this distinction may therefore be somewhat misleading, but I have gone with dividing them according to articulation for these rather than behavior in a syllable.

The prototypical vowels are /i/, /ɯ/, /a/ but there is a lot of variation in exact pronunciation due to phonemeic environment and dialect
Mindakri
Tnaaq
Luquv
Lixaanu hal-'adami
Ba'eni
Kaingu
Ame language
/a e i o/, with length distinction

/o/ might be [u] after /h/, in which case /h/ becomes [ɸ], making the combination /ho/ pronounced as [ɸu]
Classical Uraki
Iloyan
Gjeyejz-sjayajz
Abasut
Ernalan
Red Creek
Thulean
Weakwan
Tvern El
Proto-Maritime
Talbas
Etelegbe
Nanawe
Touijab Kikxot
Nyan Myat
Dwendish
Illicraic
Ixe Wa
Dwarvish
At'ik
Ḍoláh
Sonsear
Wistanian
Ilcharotic
Enlalen
Atlam
Matanin
Westlandish
Avalonian
Vowel Inventory:

SHORT VOWELS: /i, u, ɛ, ɔ/
LONG VOWELS: /eɪ, oʊ, aɪ, ɑʊ/

Phonetically, the long vowels are
diphthongs but they pattern as long
vowels.
Grayis
Asokon
Least Average
Old Drengan
’Ukana’akau
Nicho
Kobold
Wara
Ox-yew
Syt
Wild Tongue
Aats'ax
Hacklow
/i, u, ä/ plus two diphthongs /aɪ, ɑʊ/
Undercommon
Kali-Sise
MPCL(PN) /i, u, a, aɪ, aʊ/. [ɛ] is the realisation of /aɪ/ in a closed syllable. [ɔ] is the realisation of /aʊ/ in a closed syllable.
Sqopran
Free Tongue /i, u, ɛ, ɑ/. There also phonetic diphthongs, /eɪ, oʊ, aɪ, ɑʊ/, which act as phonological long vowels.
Dladwu
Ipiki
Jafian
Ngoosha
Lauvinko
Mipukwi
Wenja
Soc'ul'
Standard Knrawi
mollydot's first go
Vrkhazhian
Keeltyewarem

Natlangs (20):
Abkhaz
Awa Pit
Berber (Middle Atlas)
Gooniyandi
Greenlandic (West)
Kayardild
Koasati
Kutenai
Malagasy
Martuthunira
Ngiyambaa
Nunggubuyu
Oneida
Paumari
Piraha
Rama
Shipibo-Konibo
Tiwi
Wichita
Cree (Plains)