In my experiences - about 50mw....lower if you look right down the barrel towards the dot - but that is not too fun - it's more fun for people to see the beam and go, " Ooooo...I want one !"
i had a 35mW that was visible in light, just not flouresent light, in floursesnt you could only see the dust crossing hte path and a dim beam if it had brand new batteries.