The Box Drawing block spans U+2500U+257F, 128 codepoints in Plane 0 (Basic Multilingual Plane). Every one of them is assigned in Unicode 16.0.

All of its characters have the script value Common: they are shared across writing systems rather than tied to one.

By general category: 128 other symbols (So).

The first 128 arrived in Unicode 1.1 (1993).