Angle symbol
The angle symbol ∠ marks the corner where two lines meet — the opening between them, measured in degrees. It sits in front of the corner it names: ∠ABC is the angle at B, between the arms running to A and C. Copy ∠ here with its whole geometry family — the measured angle ∡, the spherical angle ∢ and the right-angle mark ∟ — plus the notation rules that keep homework and documents correct.
Copy the angle signs
Angles at work, ready to copy
Four signs, four corners of the story
| Sign | Its name and job |
|---|---|
| ∠ (U+2220) | The plain angle — the corner itself, named before or without a measurement |
| ∡ (U+2221) | The measured angle — the corner carrying a specific value, as in ∡ 37° |
| ∢ (U+2222) | The spherical angle — between two planes or arcs, met in astronomy and advanced geometry |
| ∟ (U+221F) | The right-angle mark — the little square drawn at a 90° corner to certify it |
Three landmarks rule every angle you will meet: 90° is the right angle (a squared corner), 180° is a straight line, and 360° is the full turn home. Anything narrower than 90° is acute, anything wider is obtuse, and past 180° an angle turns reflex. The measures themselves are written with the degree sign — which has its own page here — or in radians, where the half-turn is written π.
How to type it
| Platform | Method |
|---|---|
| Windows (Word) | Type 2220 then Alt + X (2221 gives the measured angle ∡) |
| Mac | No single key — Character Viewer (search “angle”) or copy from here |
| HTML / LaTeX | HTML: the “ang” entity name (ampersand + ang;) or code 8736. LaTeX: \angle, and \measuredangle for ∡ |
| Geometry software | Tools like GeoGebra insert ∠ from their symbol palettes; in plain text and documents, paste it from here |
Explore more
The measure after the sign lives on the degree symbol page, the radian half-turn belongs to the pi symbol, and the full notation family gathers in the math symbols collection.
Frequently asked questions
How do you read ∠ABC aloud?
“Angle A-B-C” — and the middle letter is always the vertex, the corner point itself. The two outer letters name points along the arms. ∠ABC and ∠CBA are the same corner named from opposite directions; the B never moves from the middle.
∠ or ∡ — what is the difference?
∠ is the angle as a shape; ∡ is that angle with a measurement attached — “measured angle”. Many textbooks use ∠ for both and let the number do the talking, but where the distinction is kept, ∡ always travels with a value.
What is the little square at a right angle called?
The right-angle mark ∟ — a miniature square drawn into the corner to certify exactly 90° without writing a number. One glance at the square settles what a protractor would otherwise have to prove.
Why do angles use degrees and radians?
Degrees split the full turn into 360 parts — an ancient, surveyor-friendly count. Radians measure by the radius itself: the full turn is 2π, the half-turn π — the natural unit once angles enter calculus and waves. The angle symbol ∠ serves both systems alike.