Calculator Uni

Arc Length Calculator

Get arc length, chord, and sector area from radius and angle.

Circle sector
°

Arc length

10.472

s = rθ

Sector area

52.3599

Chord length

10

Share of full circle

16.7%

Slices of a circle

An arc is the fraction of circumference the angle claims: 60° is a sixth of the circle, so its arc is 2πr/6. In radians the formula collapses to s = rθ — the very reason radians exist. Sector area scales the same way: half r² θ.

Arcs in the wild

Curved driveways, pizza slices, gauge dials, and road-bend lengths are all sector math. The chord — the straight line between arc endpoints — is what you'd measure with a ruler, and the gap between chord and arc is how much a curve 'bulges.'

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