Inputs
Results
Solid angle
--
sr
Candela
--
cd
Lumens
--
lm
Calculation mode
--
Assumption note
--
Calculation details
- Solid angle
- -- sr
- Candela
- -- cd
- Lumens
- -- lm
- Calculation mode
- --
- Assumption note
- --
Important notes
- Beam angle definitions vary by product and test method; use manufacturer photometry for design decisions.
- This calculator is planning support only and does not declare compliance.
Formulas
- \(\displaystyle \Omega = 2\pi(1-\cos(\theta/2))\)
- \(\displaystyle \Phi = I \times \Omega\)
- This is a geometric approximation and not a substitute for measured photometry.
Estimate the approximate relationship between lumens and candela from a simple beam-angle solid angle.
Candela and Lumens Relationship Calculator is a planning aid. Keep the target source, product data, measurement method, and project assumptions with the result. Confirm compliance, installation, certification, and safety decisions with the responsible professional.