Arc Length Calculator
Calculate the length of a circular arc and its chord from the radius and the central angle in degrees. Enter radius and central angle to see arc…
8 of 8 free uses remaining today
Calculate the length of a circular arc and its chord from the radius and the central angle in degrees. Enter radius and central angle to see arc length and chord length when you calculate.
Worked example
Example calculated from the starting values. Enter your own values and press Calculate to get your result.
With the default inputs (radius = 10, central angle = 90 degrees), the results are: arc length 15.708; chord length 14.142.
Quick reference: radius vs result
Reference table based on the example values; it is not your calculation result.
| Radius | Arc length | Chord length |
|---|---|---|
| 5 | 7.854 | 7.071 |
| 10 | 15.708 | 14.142 |
| 20 | 31.416 | 28.284 |
| 50 | 78.540 | 70.711 |
| 100 | 157.080 | 141.421 |
| 200 | 314.159 | 282.843 |
Frequently asked questions
What formula does this calculator use?
Arc length = 2 × pi × r × ang ÷ 360; Chord length = 2 × r × sin(ang × pi ÷ 360). Variables: r = radius, ang = central angle in degrees.
What do I need to enter?
You need radius, central angle (degrees). Results update as you type.
What is an example result?
With the default inputs (radius = 10, central angle = 90 degrees), the results are: arc length 15.708; chord length 14.142.
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