A large part of it depends on which ribs you broke. The higher ones move less and hurt less than the lower ones. I broke 9, 10, and 11 all in a row on my left side and was riding in 4 weeks but they still hurt a lot (but I never went to the doctor and didn't "know" what I had broken). Two months later I broke 6 and 7 along with my collar bone. The collar bone kept me off the bike for 5 1/2 weeks and when I rode again I didn't even notice the ribs.
Since I had to go to the ER with the obviously broken collar bone, the doctor came in with the x-rays and said, "Yep, you broke your collar bone and ribs 6 and 7. And 9, 10, and 11 are healing nicely." All 5 were broken in a straight line down the left side.
Bottom line is, though, no one but your doctor can give you any decent advice on when you can ride again safely.