The Greek alphabet.

Ancient and medieval letters.

The Greek alphabet has 24 letters. Each letter has an uppercase and a lowercase form.

Letter. Name. Pronunciation.
Α α ἄλφα alpha a as in father
Β β βη̂τα beta b as in boy
Γ γ γάμμα gamma g as in girl
ng as in ring
Δ δ δέλτα delta d as in dog
Ε ε ἒ ψιλόν epsilon e as in get
Ζ ζ ζη̂τα zeta sd as in wisdom
Η η ἠ̂τα eta e as in there
Θ θ θη̂τα theta th as in top
Ι ι ἰω̂τα iota i as in magazine
Κ κ κάππα kappa k as in racket
Λ λ λάμβδα lambda l as in lamb
Μ μ μυ̂ mu m as in mother
Ν ν νυ̂ nu n as in nice
Ξ ξ ξι̂ xi x as in fox
Ο ο ὂ μικρὸν omicron o as in not
Π π πι̂ pi p as in pig
Ρ ρ ρ̒ω̂ rho r as in river
Σ σ
ς*		 σίγμα sigma s as in silly,
s as in miasma
Τ τ ταυ̂ tau t as in until
Υ υ ὒ ψιλόν upsilon u as in tune
Φ φ φι̂ phi ph as in pot
Χ χ χι̂ chi kh as in kit
Ψ ψ ψι̂ psi ps as in maps
Ω ω ὠ̂ μέγα omega o as in doze
 
* At the beginning or in the middle of a word the letter is σ (initial or medial sigma). At the end of a word it is ς (final sigma).

Greek vowels can often come together to make new sounds, called diphthongs.

Diphthong. Pronunciation.
αι ai as in aisle
αυ ow as in how
ει ei as in their
ευ ew as in drew
ηυ ew as in pew
οι oi as in oil
ου ou as in youth
υι we as in weak
   
ᾳ long a
ῃ long e
ῳ long o

Those last three diphthongs are each a long vowel with an iota subscript, an iota written underneath the letter. The ancient Greeks would pronounce the iota, but we no longer do.

Any vowel or diphthong at the beginning of a word requires a breathing. There are two breathings, smooth and rough.

ἐν en
ε̒ν hen

There is no letter for the h sound in Greek, but the rough breathing substitutes for one.