Originally Posted by
topflightpro
Specialized has the pad for measuring hip bone width to help you identify which saddle width is appropriate for you.
That said, there is no real science to saddle fitting. It's really personal preference. Many shops have demo saddles or old saddles you can borrow to try out. Ask friends to try their saddles. Or buy from places with a good return policy.
I've done this at my LBS and ended up with a 155MM Specialized Toupe; which so far has been great. It isn't the most scientific process but seemed to work well. Echoing a lot of comments already made, most reputable shops will have a generous return policy so you can try out a few until you've found the one.
For the OP, what are you trying to address with replacing or getting fit for a saddle?