0603 is in mils. The first numbers (06) is the length and means 60 mils and the second two (30) are the width and mean 30 mils. So an 0603 component is a MAXIMUM of 60 mils x 30 mils. If you wanted to measure on a component, you would want a 50 mil pitch and if you wanted to measure on the pads, you could probably use 40, 50 or 60 mil pitch. Ideal would still be 50 mils so that the ports are in the same place on the component as they attach on the printed circuit board.
So for 0603 I would likely choose a 50 mil probe pitch.
0603 is in mils. The first numbers (06) is the length and means 60 mils and the second two (30) are the width and mean 30 mils. So an 0603 component is a MAXIMUM of 60 mils x 30 mils. If you wanted to measure on a component, you would want a 50 mil pitch and if you wanted to measure on the pads, you could probably use 40, 50 or 60 mil pitch. Ideal would still be 50 mils so that the ports are in the same place on the component as they attach on the printed circuit board.
So for 0603 I would likely choose a 50 mil probe pitch.