The Combining Diacritical Marks for Symbols block spans U+20D0–U+20FF, 48 codepoints in Plane 0 (Basic Multilingual Plane). 33 are assigned in Unicode 16.0; the other 15 are reserved for future characters.

All of its characters belong to the Inherited script.

By general category: 26 non-spacing marks (Mn), 7 enclosing marks (Me).

The first 18 arrived in Unicode 1.1 (1993); later additions came in 3.0 (2), 3.2 (7), 4.1 (1), 5.0 (4), 5.1 (1).

Most characters here are combining marks. See combining diacritical marks.