△
△ Triangle Symbol
The triangle symbol (△) is the geometric triangle used in notation like △ABC. It is a different character from the Greek capital delta Δ, which means “change in”.
Also known as: triangle symbol, triangle sign, white up-pointing triangle, geometry triangle symbol.
Codes
| Symbol | △ | |
| Filled | ▲ · U+25B2 | |
| Unicode | U+25B3 | |
| HTML entity (decimal) | △ | |
| HTML entity (hex) | △ | |
| CSS | \25B3 | |
| LaTeX | \triangle |
How to type △ (Triangle Symbol)
Windows25B3, Alt + X
In Word, type 25B3 then press Alt + X. Elsewhere, copy △ above or use Character Map.
Mac
Open Character Viewer (Control + Cmd + Space) and search “triangle”, or copy △ above.
Microsoft Word25B3, Alt + X
Type 25B3, then press Alt + X to convert it to △.
Google Docs
Insert → Special characters, then search “triangle” (or draw one in the sketch box).
LaTeX\triangle
Use \triangle in math mode: \triangle ABC. \bigtriangleup draws a larger one.
Usage
- In geometry, △ABC names the triangle with vertices A, B and C: “△ABC is congruent to △DEF”.
- △ vs Δ — the trap worth knowing. △ (U+25B3) is a shape. Δ (U+0394) is the Greek capital delta, and in math and science it means “change in”: Δx is a change in x, not a triangle. They are different characters and are not interchangeable, however similar the glyphs look.
- ▲ (U+25B2) is the filled version, used in UI as a sort or expand indicator rather than in math.
- Turned the other way up, ∇ (U+2207) is nabla — a differential operator, not a shape.