Skip to main content

learn.howToCalculate

learn.whatIsHeading

Calculates the area of a circular sector (pie-slice shaped region) given radius and angle. A sector is defined by two radii and the arc between them.

Fórmula

A = (θ/360°) × πr² for degrees; A = ½r²θ for radians
r
radius (length)
θ
central angle (degrees or radians)
A
sector area (length²)

Guia passo a passo

  1. 1Area = (θ/360) × πr² for degrees
  2. 2Area = ½r²θ for radians
  3. 3Full circle = 360° = 2π radians
  4. 4Half circle sector = semicircle

Exemplos resolvidos

Entrada
r = 8, θ = 45°
Resultado
Area = (45/360)×π×64 ≈ 25.13
Entrada
r = 6, θ = 2 rad
Resultado
Area = ½×36×2 = 36

Perguntas frequentes

Can I calculate sector area if I only know the arc length?

Yes: if arc = a and radius = r, then A = ½ × r × a.

What fraction of the circle is a 60° sector?

60°/360° = 1/6 of the circle, so area = (1/6)πr².

Why are there two formulas for sector area?

One uses degrees (dividing by 360), the other uses radians (multiplying by 1/2). Use whichever unit your angle is in.

Pronto para calcular? Experimente a calculadora Sector and Arc gratuita

Experimente você mesmo →

Configurações

PrivacidadeTermosSobre© 2026 PrimeCalcPro