Arc Length Calculator
⬛ Area & perimeter (2D). Use the Arc length formula to find arc length, angle θ, radius: pick the value you want, type the others, and the answer updates as you go.
Arc length5.236 cm
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Arc length | cm |
| Angle θ | ° |
| Radius | cm |
Worked example
Find the arc length when Angle θ = 60 °, Radius = 5 cm.
Using L = θ/360 × 2π r: Arc length = 5.236 cm.
Frequently asked questions
What is the formula for Arc length?
L = θ/360 × 2π r.
What do the letters stand for, and what units are used?
Arc length in cm, Angle θ in °, Radius in cm.
How do you calculate arc length?
Put the values into L = θ/360 × 2π r. For example, with Angle θ = 60 °, Radius = 5 cm, arc length = 5.236 cm.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (arc length, angle θ, radius) and fill in the others: it rearranges the formula for you.
