Sector Calculator (A = θπr²/360)

Quick answer

This calculator computes the sector area and arc length: exact formula A = θπr²/360, worked example r = 6 cm, θ = 60° → A = 18.85 cm², arc = 6.28 cm.

Free, instant, any units.

Figures are estimates from this calculator’s standard formula — adjust the inputs in the tool below for your exact number.

How the sector area and arc length Calculator Works

A = (θ/360)·πr², arc = (θ/360)·2πr

The calculator applies the exact formula A = (θ/360)·πr², arc = (θ/360)·2πr. Worked example: r = 6 cm, θ = 60° → A = 18.85 cm², arc = 6.28 cm. Keep every input in one unit system and the result follows in square units (m², ft², cm²); full precision is kept until the final rounding. All side lengths must share one unit or the area comes out scaled wrongly.

1
Enter the measurements
Type the values required by the formula for sector area and arc length.
2
Check the units
One unit system throughout — cm, m, ft or in.
3
Read the result
The calculator substitutes, evaluates and rounds only at the end.

Use Cases

Floor, plot and panel measurements

School geometry and land surveying

Double-checking material orders and quotes

Tips

1
Area scales with the square of linear dimensions
2
1 m² = 10.764 ft² for quick conversion
3
Sketch and label the shape before entering values

Common Mistakes

Unit mix-ups between cm² and m² (factor 10,000)
Using a slanted length as a perpendicular height
Treating an irregular shape as regular

FAQs

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