This arc length reference table shows the arc length for a range of radius values, assuming a central angle of 90 degrees. Every figure is computed with the same engine that powers our Arc Length Calculator, so the numbers are exact.
| Radius | Arc length |
|---|---|
| 1.5 units | 2.3562 |
| 3 units | 4.7124 |
| 4.5 units | 7.0686 |
| 6 units | 9.4248 |
| 9 units | 14.1372 |
| 12 units | 18.8496 |
| 18 units | 28.2743 |
| 30 units | 47.1239 |
| 42 units | 65.9734 |
| 60 units | 94.2478 |
How to use this table
Find the row closest to your radius and read across to the arc length. For a value between two rows, the real figure sits between them — or enter your exact numbers in the Arc Length Calculator for a precise answer.
Need a value that is not in the table? — the Arc Length Calculator does it instantly, for free, with the formula and a worked example built in.
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