A diphthong is a single-syllable vowel sound that glides from one vowel sound to another. There are eight common diphthongs in American English that are represented by specific letter combinations and vowel sounds. Diphthongs combine two vowel sounds within one syllable to create a gliding effect between the sounds.

1. Diphthong
What is a diphthong?
A diphthong is a single-syllable vowel sound in which the beginning of the sound is different from the end
sound—that is, the sound glides from one vowel sound to another. For this reason, diphthongs are often referred to
as gliding vowels.
 A diphthong combines two vowels to create one sound.
 The diphthongs are all long sounds.
 The tongue and the mouth move from one position to another to form a diphthong, as in the following.
A “pure” vowel sound that doesn’t glide is known as a monophthong. A single syllable that glides between three
vowel sounds; this is known as a triphthong.
There are eight vowel sounds in American English that are generally agreed upon as being diphthongs.
With the exception of long E (/i/), all of the traditional long vowel sounds are diphthongs. These most
predictably occur when the vowel letter is followed by a single consonant and a silent “e”:
Vowel Letter Vowel Sound (IPA Symbol) How to pronounce it Example
A /eɪ/ eh-ee tape(/teɪp/)
I /aɪ/ ah-ee ice(/aɪs/)
O /oʊ/ oh-oo rope(/roʊp/)
U /ju/* ee-oo Cube (/kjub/
/ɔɪ/
This diphthong is pronounced “au-ee”—it begins with the /ɔ/ sound (as in dawn or door) and glides to the /ɪ/
sound (as in pit). It generally only occurs with the vowel combinations “OY” and “OI.”
Common
Digraphs
Example / IPA Example / IPA Example / IPA
OY
Boy-/bɔɪ/, annoy-/əˈnɔɪ/ Royal- /ˈrɔɪəl/
employed -/ɪmˈplɔɪd/
OI Coin-/kɔɪn/, noise-/nɔɪz/ Foil-/fɔɪl choice -/ʧɔɪs/
/aʊ/
This diphthong is pronounced “ah-oo”—the vowel glides from the /æ/ sound (as in bat) to the /ʊ/ sound (as in
pull). It generally occurs with the digraphs “OU” and “OW.”
Common
Digraphs
Example / IPA
Example / IPA Example / IPA
OU
Found-/faʊnd/
Pout-/paʊt/, mouth-/maʊθ/
drought- /draʊt/ (GH
becomes silent)
OW Town/taʊn/, Crowd-/kraʊd/, shower-/ˈʃaʊər/ chowder -/ˈʧaʊdər/

2. R-Colored” Diphthongs
There are two other diphthongs that sometimes occur in American English: /ɪə/ and /ɛə/. These can be found in
certain instances where a vowel sound is followed by an “r.” However, it is very common in General American
pronunciations to omit the schwa sound before the “r” in /ɪər/ and /ɛər/, and the standard transcription in (most)
American dictionaries is often simply /ɪr/ or /ɛr/, respectively.
R-Colored” Diphthongs, /ɪə/
When this diphthong is articulated, it is pronounced “ih-uh,” quickly gliding from the short I sound /ɪ/ (as in tip)
to an unstressed schwa (/ ə/). It usually occurs with the digraphs “EE,” “EA,” and “IE” when they are followed
by an “R.”
Letter
Combinations
Example / IPA Example / IPA Example / IPA
EER Beer-/bɪər/, deer-/dɪər/ Sheer- /ʃɪər/ steer- /stɪər/
EAR Dear-/dɪər/, hear-/hɪər/ shear -/ʃɪər/ Appear-/əpˈɪər/
IER* Pier-/pɪər/, fierce-/fɪərs/ frontier -/frənˈtɪər/ Bandolier-/ˌbændəˈlɪər/
R-Colored” Diphthongs, /ɛə/
When this diphthong is articulated, it is pronounced “eh-uh,” quickly gliding from the short “E” sound /ɛ/ (as in
set) to an unstressed schwa(/ə/).
This diphthong usually occurs with the letter combinations “ARE” and “AIR,” but be careful: it also sometimes
occurs with “EAR,” which is often pronounced /ɪər/.
Letter
Combinations
Example/ IPA Example/ IPA Example/ IPA
ARE* Flare-/flɛər/, care-/kɛər/ stare -/stɛər/ ensnare- /ɪnˈsnɛər/
AIR
Flair-/flɛər/, stairs-/stɛərz/ dairy- /dɛəri/ Repair-/rəˈpɛər/
EAR
Wear-/wɛər/, bear-/bɛər/,
pear -/pɛər/, swear- /swɛər/ tear -/tɛər/
Diphthong Vowels | Sounds
✦ A diphthong is a long vowel that moves from one mouth position to another. The first position in a
diphthong is stronger than the second.
IPA
Symbol
Sound Pronunciation Spellings Examples
eɪ ay eh-ee ay, ea, a e, ai pay, great, maid
ɔɪ oy au-ee oi, oy noise, toy, choice
aɪ ai ah-ee ie, i_e, i, y fine, like, might
əʊ oh [oʊ] oh-oo o, o_e, oa, ow no, stone, road
aʊ ow ah-oo ou, ow round, how, brown
ɪə ih-uh eer, ear beer, hear, steer
eə
eh-uh are, ere, ea, ai care, there, bear

3. Diphthongs (oʊ, aʊ, aɪ, eɪ, ɔɪ, ju)
[oʊ] – The OH as in NO Diphthong
Soundː oh [oʊ]
Spelling: o: go [goʊ], oo: brooch [bɹoʊʧ], ou: soul [soʊl], ow: row [ɹoʊ], oa: oat [oʊt], oe: foe [foʊ], ough:
though [ðoʊ], au: chauffeur [ˈʃoʊ fəəɹ], eau: beau [boʊ]
oh [oʊ] Stressed oh [oʊ] Unstressed oh [oʊ] Stressed oh [oʊ] Unstressed
go [goʊ] borrow [ˈbɑɹ oʊ] know [noʊ] yellow [ˈjɛl oʊ]
below [bɪˈloʊ]
[aʊ] – The OW as in NOW Diphthong
Soundː ow [aʊ]
Spelling: ou: round [ɹaʊnd], ow: cow [kaʊ], ough: bough [baʊ]
ow [aʊ] Stressed ow [aʊ] Unstressed ow [aʊ] Stressed ow [aʊ] Unstressed
now [naʊ] letdown [ˈlɛt￨ daʊn] sound [saʊnd] blackout [ˈblæk aʊt]
power [ˈpaʊ əəɹ]
[aɪ] – The AI as in BUY Diphthong
Soundː ai [aɪ]
Spelling: y: my [maɪ], ai: aisle [aɪl], ie: lie [laɪ], ye: bye [baɪ], uy: buy [baɪ], igh: sight [saɪt], eigh: height [haɪt],
aye: aye [aɪ], i: time [taɪm]
ai [aɪ] Stressed ai [aɪ] Unstressed ai [aɪ] Stressed ai [aɪ] Unstressed
mind [maɪnd] idea [aɪˈdi əə] united [juˈnaɪ dɪd] exercise [ˈɛk səəɹˌsaɪz]
[eɪ] – AY as in SAY Diphthong
Soundː ay [eɪ]
Spelling: a: age [eɪʤ], ai: aid [eɪd], ay: say [seɪ], eight: eight [eɪt], ey: they [ðeɪ]
ay [eɪ] Stressed ay [eɪ] Unstressed ay [eɪ] Stressed ay [eɪ] Unstressed
play [pleɪ] highway [ˈhaɪ weɪ] stay [steɪ] always [ˈɔl weɪz]
late [leɪt]
[ɔɪ] – The OY as in TOY Diphthong
Soundː oy [ɔɪ]
Spelling: oi: moist [mɔɪst], oy: boy [bɔɪ]
oy [ɔɪ] Stressed oy [ɔɪ] Unstressed oy [ɔɪ] Stressed oy [ɔɪ] Unstressed

4. toy [tɔɪ] steroid [ˈstɛɹ ɔɪd] employs [ɛmˈplɔɪz] envoy [ˈɑn vɔɪ]
voice [vɔɪs]
[ju] – The EW as in FEW Diphthong
Soundː ew [ju]
Spelling: u: use [juz], eu: feud [fjud], ew: few [fju], eau: beauty [ˈbju di]
ew [ju] Stressed ew [ju] Unstressed ew [ju] Stressed ew [ju] Unstressed
few [fju] U. S. [juˈɛs] beauty [ˈbju di] January [ˈdʒæn ju ˌɛɹ i]
view [vju]