They're typically between the size of a 1-2p coin and the first joint
of the index finger
, round or squished (although on the leg, they can be much larger), and never painful. I wouldn't call these accident bruises, cos I tend to remember my ridiculous accidents, and even if you walk into a table, those suckers hurt, which these don't. Given how accident prone I am, I still don't GET 'random bruises'. I remember. I bruise easily.