The Phonetic Extensions block spans U+1D00–U+1D7F, 128 codepoints in Plane 0 (Basic Multilingual Plane). Every one of them is assigned in Unicode 16.0.
By script: Latin (111), Greek (15), Cyrillic (2).
By general category: 64 lowercase letters (Ll), 64 modifier letters (Lm).
The first 108 arrived in Unicode 4.0 (2003); later additions came in 4.1 (20).
61 characters here have compatibility decompositions: they are formatting variants of other characters and are replaced by them under NFKC and NFKD. See normalization.