Geometric Shapes
Squares, circles, triangles and diamonds, solid and outlined, small and large: Unicode’s geometric shapes block gives plain text a full set of basic marks, useful anywhere a document needs a bullet, a rating marker, or a simple icon without loading an image.
None of these have a Windows Alt code, though a few common ones, the solid black square among them, survive from the original DOS character set and keep a code for that reason alone.
Questions
Is there an Alt code for a solid black square?
Yes, one of the few shapes here with a genuine DOS-era code, Alt+254. Most other shapes have no Alt code at all.
What is the difference between a shape and its outlined version?
They are separate Unicode characters. A solid black square and a white outlined square each have their own code point, not a style applied to one shape.
Are these shapes the same as emoji shapes?
Some overlap with emoji sets, but the characters here are the plain text geometric shapes block, which renders consistently as text rather than a colour icon.
Is there an Alt code for a solid black circle?
No. Copy the character directly, or use the HTML entity ● or the Unicode value U+25CF.
Why are there both small and large versions of the same shape?
Unicode gives different sizes of the same basic shape their own code point, a small and a large black square, for instance, so text can show a size difference without relying on font styling.