Arc length
Find the length along a circular arc.
Inputs
Use the units shown—
Enter your values and select Calculate.
Formula & explanation
L = (θ/360)2πr
Variables & units
- Radius
- cm · minimum 0, maximum 1000000000
- Central angle
- ° · minimum 0, maximum 360
Worked example
Radius 3 cm and angle 60° give an arc length of π cm.
Assumptions
Arc length follows the curve; it is not the straight chord.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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