Tense Vowels and Diphthongs

		Front	Central	Back
High	Tense	iy (sea) ir (here)		uw (to) ur (moor)
Mid	Tense	ey (age) er (hair)		ow (go) oy (boy) or (for)
Low	Tense

Sounds of American English

Merriam Webster Pronouncing Dictionary

Bartleby's Pronouncing Dictionary
(Includes Technical Words)

The Free Dictionary