α β γ δ ε ϝ ϛ ζ η θ ι κ λ μ ν ξ ο π ϟ ϙ ρ σ τ υ φ χ ψ ω ϡ

Without uppercase
ϳ ϗ

Characters not recommended
͵ ϶

Decomposable
ἀ ἄ ἂ ἆ ἁ ἅ ἃ ἇ ά ὰ ᾰ ᾶ ᾱ ἐ ἔ ἒ ἑ ἕ ἓ έ ὲ ἠ ἤ ἢ ἦ ἡ ἥ ἣ ἧ ή ὴ ῆ ἰ ἴ ἲ ἶ ἱ ἵ ἳ ἷ ί ὶ ῐ ῖ ϊ ΐ ῒ ῗ ῑ ὀ ὄ ὂ ὁ ὅ ὃ ό ὸ ῤ ῥ ὐ ὔ ὒ ὖ ὑ ὕ ὓ ὗ ύ ὺ ῠ ῦ ϋ ΰ ῢ ῧ ῡ ὠ ὤ ὢ ὦ ὡ ὥ ὣ ὧ ώ ὼ ῶ

IDN-Remapped-Case
Α Β Γ Δ Ε Ϝ Ϛ Ζ Η Θ Ι Κ Λ Μ Ν Ξ Ο Π Ϟ Ϙ Ρ Σ ς Τ Υ Φ Χ Ψ Ω Ϡ

IDN-Remapped-Case-Decomposable
Ἀ Ἄ ᾄ ᾌ Ἂ ᾂ ᾊ Ἆ ᾆ ᾎ ᾀ ᾈ Ἁ Ἅ ᾅ ᾍ Ἃ ᾃ ᾋ Ἇ ᾇ ᾏ ᾁ ᾉ Ά ᾴ Ὰ ᾲ Ᾰ ᾷ Ᾱ ᾳ ᾼ Ἐ Ἔ Ἒ Ἑ Ἕ Ἓ Έ Ὲ Ἠ Ἤ ᾔ ᾜ Ἢ ᾒ ᾚ Ἦ ᾖ ᾞ ᾐ ᾘ Ἡ Ἥ ᾕ ᾝ Ἣ ᾓ ᾛ Ἧ ᾗ ᾟ ᾑ ᾙ Ή ῄ Ὴ ῂ ῇ ῃ ῌ Ἰ Ἴ Ἲ Ἶ Ἱ Ἵ Ἳ Ἷ Ί Ὶ Ῐ Ϊ Ῑ Ὀ Ὄ Ὂ Ὁ Ὅ Ὃ Ό Ὸ Ῥ Ὑ Ὕ Ὓ Ὗ Ύ Ὺ Ῠ Ϋ Ῡ Ὠ Ὤ ᾤ ᾬ Ὢ ᾢ ᾪ Ὦ ᾦ ᾮ ᾠ ᾨ Ὡ Ὥ ᾥ ᾭ Ὣ ᾣ ᾫ Ὧ ᾧ ᾯ ᾡ ᾩ Ώ ῴ Ὼ ῲ ῷ ῳ ῼ

IDN-Remapped-Compat
ʹ ά Ά ϐ ϵ έ Έ ή Ή ϑ ϴ ι ί Ί ΐ ϰ ό Ό ϖ ϱ ϲ ϒ ύ Ύ ϓ ϔ ΰ ϕ Ω ώ Ώ

Important note:
the characters not supported by UTF-8 Unicode are the red ones.