How do you calculate the area of a circle?

The area of a circle is A = πr², where r is the radius. If you know the diameter, divide by 2 to get the radius first. This calculator shows the full computation.

Arc length is the distance along a curved section of a circle. It equals (θ/360°) × 2πr for a central angle θ in degrees, or simply θr when θ is in radians.

How do you find sector area?

Sector area is the region enclosed by two radii and an arc. The formula is (θ/360°) × πr² for degrees, or (1/2)r²θ for radians. This calculator breaks the computation into clear steps.

Circle Calculator

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About Circle Calculator

Enter a radius, diameter, or angle to compute area, circumference, arc length, sector area, and chord length with step-by-step formulas and visual diagrams. Ideal for geometry homework or quick reference on circle properties.

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FAQ

Is this geometry calculator free?

Yes! The Geometry & Trig Calculator provides free step-by-step solutions for triangles, circles, angles, trig functions, and shape measurements. No account required.

What types of geometry problems can it solve?

It covers angle operations (addition, conversion, complements), circle calculations (area, circumference, arc length), triangle solving (law of sines/cosines, Pythagorean theorem), trigonometric functions, coordinate geometry (distance, midpoint, slope), and 2D/3D shape measurements.

How does the calculator work?

It uses precise mathematical formulas and Python's math library to compute exact results. Unlike AI chatbots, every answer is deterministic and mathematically guaranteed to be correct.

Does it show formulas and step-by-step work?

Yes! Every solution includes the formulas used, substituted values, and a clear breakdown of each calculation step so you can follow along and learn.

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