**Related Resources: math**

### Circular Segment Equation and Calculator

Circular Segment Equation and Calculator

Circular segment is a region of a circle which is "cut off" from the rest of the circle by a secant or a chord . More formally, a circular segment is a region of two-dimensional space that is bounded by an arc (of less than 180°) of a circle and by the chord connecting the endpoints of the arc.

Where:

**Radius:**

R = h + d = h / 2 + c^{2} / ( 8h )

**Arc Length:**

s = arcsin ( c / ( h + c^{2} / 4h ) ) ( h + c^{2} / 4h )

**Chord Length: θ given in radians.**

c = 2 R sin ( θ / 2 )

* Angle*:

θ = 2 arctan ( c / ( 2 d ) )

** Sagitta: θ given in radians.**

h = R ( 1 - cos ( **θ** / 2) )

**Area: **

The area A of the circular segment is equal to the area of the circular sector minus the area of the triangular portion. **θ** given in radians.

**A = (R ^{2} / 2 ) ( θ - sinθ )**

Central angle in radians

**A = ( R ^{2} / 2 ) ( ( α Π ) / 180° - sinθ )**

Central angle in degrees