The CJK Unified Ideographs Extension I block spans U+2EBF0–U+2EE5F, 624 codepoints in Plane 2 (Supplementary Ideographic Plane). 622 are assigned in Unicode 16.0; the other 2 are reserved for future characters.
All of its characters belong to the Han script.
By general category: 622 other letters (Lo).
The first 622 arrived in Unicode 15.1 (2023).
622 characters are East Asian Wide or Fullwidth and take two columns in terminals.
Because it lies outside the BMP, every character here takes four bytes in UTF-8 and a surrogate pair in UTF-16.