Which shutter speed is not a full stop?

f/1, f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, f/32 are the usual full stops in aperture. You could have a full stop difference between two half or thirds as well.

a full stop is when the light is halved or doubled between the two settings. so in shutter speeds if the time is close to doubled or halved its considered a stop so going from 1/30th to 1/60th would be a stop and the next nominal stop down would be 1/125th of a second.