Code point
U+324A
Glyph appearance depends on your fonts.
U+324A
NoU+324A CIRCLED NUMBER THIRTY ON BLACK SQUARE is a Unicode 16.0.0 character in the Other Number category. It belongs to the Enclosed CJK Letters and Months block.
Choose the representation you need, then copy its value.
U+324A
12874
㉊
㉊
E3 89 8A
324A
0000324A
%E3%89%8A
\u324A
\u324A
\u324A
\324A