This calculator is useful for calculating the luminous flux for LEDS where the angle is known.
1 candela of luminous intensity equals 1 lumen of luminous flux per steradian of solid angle, where a steradian respresents a cone whose surface area at the end equals the length of the cone squared.
![mcd to Lumens Formula: Phi(v) = I(v) * Omega](/static/img/mcd-to-lumens-1.png)
where:
- Φv is the luminous flux, in measured in Lumens (lm),
- Iv is the luminous intensity, measured in Candela (cd), and
- Ω is the solid angle of the beam is measured in Steradian (sr).
Conversion from beam angle to solid angle (sterians) is done with this formula:
![degrees to sterians Formula: Omega = 2pi(1-cos(theta*pi/360))](/static/img/mcd-to-lumens-2.png)
where:
- θ is the the beam angle measured in degrees.
![](/static/img/mcd-to-lumens-3.png)
Enter any two known values and press "Calculate" to solve for the other.