How do i measure backspace on a set of wheels?

My buddy is selling his wheels of his wrangler but i need to know the backspacing

 

Nvm i got it

 

you should know by know look before you ask! Jp

 

and you should know how to spell

 

lol, measure from your lugs out

 

Whale aye don't can U taech me? lol I suck at spelling and plus my brain trys to get ahead of my fingers and i mess up.

 

you can also take the wheel off and put it face down on the ground, find something you can use as a straight edge, maybe a yardstick or something similar, but you would have to cut it so that it rests on the lip of the rim and not the tire, then using a ruler or a tape measure, measure from your straight edge to the mounting surface.

 

yeah i got it thanks