Lumens per watt to watts per kilolumen
Type a value in lm/W to get it in W/klm instantly.
10W/klm
That's 1.67× as efficient as a fluorescent tube, while a modern LED is 1.2× better. An 800 lumen bulb at that efficiency would draw about 8 watts.
Convert the other way: W/klm to lm/W
What it means
How efficient is that?
The 683 lm/W ceiling is for pure 555 nm green light. Any usable white light must spread across the spectrum, so about 250–350 lm/W is the practical limit.
The math
How to convert lm/W to W/klm
Watts per kilolumen is the reciprocal of lumens per watt: W/klm = 1000 ÷ (lm/W). The percentage is against the 683 lm/W ceiling.
Example: 100 lm/W = 10 W/klm.
Every unit
Your efficacy in every unit
Tables
lm/W to W/klm conversion table
| lm/W | W/klm |
|---|---|
| 5 lm/W | 200 W/klm |
| 10 lm/W | 100 W/klm |
| 15 lm/W | 66.6667 W/klm |
| 25 lm/W | 40 W/klm |
| 50 lm/W | 20 W/klm |
| 75 lm/W | 13.3333 W/klm |
| 100 lm/W | 10 W/klm |
| 150 lm/W | 6.66667 W/klm |
| 200 lm/W | 5 W/klm |
| 300 lm/W | 3.33333 W/klm |
| 683 lm/W | 1.46413 W/klm |
W/klm to lm/W conversion table
| W/klm | lm/W |
|---|---|
| 5 W/klm | 200 lm/W |
| 10 W/klm | 100 lm/W |
| 15 W/klm | 66.6667 lm/W |
| 25 W/klm | 40 lm/W |
| 50 W/klm | 20 lm/W |
| 75 W/klm | 13.3333 lm/W |
| 100 W/klm | 10 lm/W |
| 150 W/klm | 6.66667 lm/W |
| 200 W/klm | 5 lm/W |
| 300 W/klm | 3.33333 lm/W |
| 683 W/klm | 1.46413 lm/W |
Quick answers
Quick answers
- How many W/klm is 1 lm/W?
- 1 lm/W is 1,000 W/klm.
- How many W/klm is 10 lm/W?
- 10 lm/W is 100 W/klm.
- How many W/klm is 100 lm/W?
- 100 lm/W is 10 W/klm.
The units
About these units
Lumens per watt (lm/W)
The standard measure of lighting efficiency.
Watts per kilolumen (W/klm)
Turned around: the power needed per thousand lumens.
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