Photometry Tools
Millicandela to Lumens Calculator
Convert directional intensity in millicandelas (mcd) to overall luminous flux in lumens (lm).
Calculation Input
Luminous Flux Output
0.00 lm
Luminous Intensity (Candelas)
0.00 cd
Solid Angle (Steradians)
0.00 sr
How Candelas and Lumens relate to Millicandelas
One millicandela ($mcd$) is one thousandth of a candela ($cd$). To convert millicandelas back to total light flux in lumens, we first divide by $1000$ to get candelas, and then multiply by the solid angle ($\Omega$) representing the cone size in steradians:
$$\Phi_{lm} = \frac{I_{mcd}}{1000} \times 2\pi \left(1 - \cos\left(\frac{\theta}{2}\right)\right)$$
Where $\theta$ is the apex beam angle in degrees. The solid angle $\Omega = 2\pi(1 - \cos(\theta/2))$.