Lumen and watt units represent different quantities, so you can't convert lumens to watts, however you can calculate watts from lumens and luminous efficacy.



The power P in watts (W) is equal to the luminous flux ΦV in lumens (lm), divided by the luminous efficacy η in lumens per watt (lm/W): P(W) = ΦV(lm) / η(lm/W)



So watts = lumens / (lumens per watt)



or W = lm / (lm/W)

That is not a valid question. Watts is power used & lumens are the amount of light emitted.

Two different beasts.





160 lumens may be output for a high efficiency lamp of X watts, but maybe X + watt-ever watts, for a low efficiency lamp. (Please pardon the pun).

lumens is different than watts. you cant convert this.