There is no general consistency between tire sizes, so a 700x30 in one brand may be the same size as a 700x32 in another brand.

However, look at your bike. Critical points are fork clearance, as well as clearance around chainstays and the brake bridge (disc brakes? that would make it easier).

a 32mm tire will be about 2mm taller and 1mm wider (each side) than a 30mm tire.

35mm tire would be about 5mm taller and 2.5mm wider (each side) than a 30mm tire.

But, of course, everything will vary somewhat.

Fenders?