Hi,
I am trying to measure the distance between 2 balss on a BGA. I want to select 2 balls, and find the distance between them. What is a good way to do it in kicad
You can either use the dimension tool (button on right hand side, black ‘N’ with dimension arrows) or just the cursor with the ‘reset readout to this position’ feature (move cursor over first ball reference, hit [SPACE] move cursor to second ball reference, check readout at bottom right of pcbnew screen (dx: … dy: … dist: …)).
I think that one is mentioned in the 101 tutorial as well 
I cant seem to find the dimension tool .WHich is it? The problem with space, is I cant select the ceter of the ball grid array correct
Are the balls on a grid that is relative to something?
Just set up the user grid spacing to the ball pitch and it’s origin to one of the balls?
I dont have that.
Oh, so you’re in the footprint editor then?
The title talked about ‘layout’, which would be PCBnew…
Yes. My bad. I meant footprint editor.
Yeah, either pull out your calculator and use the center coordinates for each ball [E] and calculate it your self or try to get used to the local coordinate read-out with the [SPACE] bar thing and some user grid - if your balls are on a non-standard grid 