Chord Length Calculator
Find the straight chord joining two points from a radius and central angle.
Formula
c = 2r sin(θ/2); θ in radians; result in cm.
Radius: 10 cm · Central angle: 60 ° · Chord length ≈ 200×(10 cm × 0.01 m/cm)×sin((60 ° × 0.01745329252 rad/°)÷2)
How to use
- Enter the radius.
- Choose the central angle and its unit.
- Read the chord length in cm.
Examples
- Radius 10 cm and angle 60° give a chord of 10 cm.
Frequently asked questions
Is this an arc length?
No. A chord is the straight segment between the arc endpoints.
Which angles are allowed?
From 0° to 360°. Reflex angles give the same chord as their complementary full-turn angle.
What is the longest chord?
The diameter, at a central angle of 180°.
Sources
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