Most of the spiders that we deal with on a day-to-day basis have 8 eyes. Some spiders have 6 eyes, while there are some spiders that have no eyes at all. Regardless of which spider you are dealing with, those spiders that do have eyes, always have an even number of eyes.
Even with that many sets of eyes, most spiders can’t see very well. Some spiders, including web building spiders, are nearly blind, using their senses of smell and touch to help them get around. Spiders that are hunting spiders usually have great eyesight.