Easily convert Lumens to Millicandela with our free calculator — just enter the lumens value, choose your beam angle, and get instant results.
Lumens to Millicandela Calculator
Convert luminous flux (lm) to luminous intensity (mcd) using a beam angle.
How to convert Lumens to millicandela
To convert lumens to millicandela (mcd) you must divide the luminous flux by the beam’s solid angle (in steradians) to get candela, then multiply by 1,000:
mcd = (lm / Ω) × 1000, where Ω (steradians) = 2π(1 − cos(θ/2)) for a circular cone with full beam angle θ.
This means there is no single mcd value for X lumens unless you know the beam angle — in a narrow beam the same lumens produce far higher mcd than when spread over a wide angle.
Millicandela to Lumens Calculator
Why lumens to millicandela depends on beam angle
“Lumens to millicandela conversion” is a geometric conversion. Lumens measure total light output; millicandela (mcd) measures luminous intensity in a direction. To get intensity from flux you must know how the flux is distributed — the beam angle determines the solid angle (steradians).
The standard cone formula is Ω = 2π(1 − cos(θ/2)). Once you have Ω:
candela (cd) = lumens (lm) / Ω
millicandela (mcd) = candela × 1000
This is the lumens to millicandela formula you’ll use in practical work and in the widget above.
How bright is 1 millicandela?
How bright is 1 millicandela?
1 mcd = 0.001 candela. A single candle is roughly 1 cd (order of magnitude), so 1 mcd is about one-thousandth of a candle’s luminous intensity.
In practice, 1 mcd is very dim — visible only at close range or in very dark conditions. Indicator LEDs are often in the tens to hundreds of mcd; very faint indicator lights or distant tiny LEDs can be ~1 mcd.
How bright is 200 mcd?
How bright is 200 mcd?
200 mcd = 0.2 candela, about one-fifth the intensity of a candle. That’s clearly visible as an indicator light in normal indoor lighting and reasonably visible outdoors in low ambient light.
Many small status LEDs (phone/indicator lights) are in the 50–500 mcd range, so 200 mcd is a practical, usable brightness for indicators.
Practical tips & use cases
- For flashlights, torches and spot LEDs, quote both lumens and beam angle — only then can you derive mcd and compare intensity.
- If you need to compare “brightness” as seen at a distance, remember luminous intensity (cd/mcd) governs how much light falls on a target at a given angle; luminous flux (lm) does not tell you directionality.
- Use the calculator to try common beam angles (10°, 30°, 60°) to see how intensity scales: smaller θ → smaller Ω → larger cd/mcd for same lumens.
Also see: Lighting Converters
FAQs
Q: Can I convert lumens to mcd without beam angle?
No — you must know how the light is distributed (beam angle) to compute steradians. A full-sphere assumption (Ω = 4π) gives a minimum intensity.
Q: Is mcd the same as lux?
No. mcd (luminous intensity) measures light per solid angle; lux measures illuminance (lm/m²) at a surface and depends on distance.
Q: What is a reasonable beam angle to test?
Common spot LEDs use 10–30°, flood lights 60–120°, and omnidirectional bulbs approach 360° (4π sr). Try these presets in the widget.
