Luminous intensity converter
Convert the brightness of a light in one direction between candela, millicandela and candlepower.
That's about the same as a candle flame. If it shone that brightly in every direction, it would give out about 12.57 lumens.
What it means
How bright is that?
Reference values are typical. Torches and headlights vary a lot with the shape of their beam.
Every unit
Your intensity in every unit
Learn
Three things worth knowing
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A candle is about one candela
That is where the unit came from. A bare bulb shining equally all round gives out 4π, about 12.6, lumens for every candela.
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From flames to a frequency
Early standards were real flames: the Hefner lamp burnt amyl acetate. Since 1979 the candela is defined as 1/683 watt per steradian of green light at 540 THz.
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Candela is not lumens
Focusing the same lumens into a narrower beam multiplies the candela. That is why a small torch can out-throw a large lamp.
Shortcuts
Popular luminous intensity conversions
Background
About luminous intensity
Luminous intensity is how bright a light looks from one direction. It is what a torch beam, a headlight or an LED datasheet is rated in, and its unit is the candela.
Total light output is a different quantity, the lumen. A laser pointer puts out almost no lumens but, straight down its beam, a very high number of candela.