Arc Length Calculator
Get arc length, chord, and sector area from radius and angle.
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.'
Frequently asked questions
- How does the Arc Length Calculator work?
- Get arc length, chord, and sector area from radius and angle.
- Is the Arc Length Calculator free to use?
- Yes. The Arc Length Calculator is completely free, runs entirely in your browser, and requires no account or sign-up. Your inputs never leave your device.
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