Skip to Content

Beam Angle & Light Spread Calculator

Calculate beam width from distance and beam angle—or determine the angle needed for your target area.

Beam Angle & Light Spread Calculator

Calculate beam width from distance and beam angle, determine the beam angle needed for a target area, or calculate the required throw distance.

Calculate Beam Width

Enter the beam angle and distance from the fixture to the target surface.

Common beam angles
Fixture 24° Beam Width 1.28 m
Beam Diameter
1.28 m
at 3.00 m throw distance
24° · Narrow Beam
Beam angle 24°
Throw distance 3.00 m
Beam diameter 1.28 m
Approx. geometric beam area 1.29 m²

Typical Applications

Practical guidance only. Manufacturers may use different beam classifications.

What Does Your Beam Angle Mean?

Narrow beams concentrate light on smaller targets, while wider beams distribute light across broader surfaces. Distance also changes the resulting beam diameter, so beam angle should always be considered together with throw distance.

Learn more about choosing 24°, 36° and 60° beam angles .

Technical Note

Results are geometric estimates based on the stated beam angle and throw distance. Beam angle is commonly defined between the directions where luminous intensity falls to 50% of maximum.

Actual appearance depends on the fixture's photometric distribution, optics, lumen output, aiming angle and target surface.

The beam-area calculation assumes a symmetrical beam aimed perpendicular to a flat target surface. For asymmetric or oval optics, refer to the manufacturer's horizontal and vertical photometric data.

Find a Fixture for Your Lighting Plan

Use your calculated beam angle and spread as a starting point, then explore Saleh Deco lighting solutions for your application.