I'm not sure about the math but I read and considered all the threads about daymakers, halide, and other off brand led's. I'll probably start a squabble here but I really didn't have a problem with the stock headlights to begin with, I just wanted to supplement them for the big stretches when I took the road trip out west. I didn't want to sacrifice the stock look or have a bunch of lights hanging all over it so my priorities were, small, aerodynamic, visually unobtrusive, and be functional for the effort to instal them. It seemed to me to be perfect on all counts. It worked way better than I expected both distance and width of beam and not only filled some of the shadow rays of the stock headlights but blended it's brighter white light with the somewhat yellowish stock lamps. It's hard to quantify but it did seem like daylight out. The thing is, there are very few places where you can turn it on without blinding the on coming traffic even on the big vast stretches out west. I'd highly recommend a separate cut-out switch. Back here on the east coast I can barely use it or it just becomes an on/off drill. I just can't imagine needing any more light than this?