How long will a broken foot be swollen after the cast comes off?

Depends. Most broken bones take around 6 weeks to mend. Ususally, there is ligamentous damage in addition that can prolong healing. As a rule of thumb, it will take two days for every one day your foot is immobilized or in a cast. (6 wks in cast 12 after cast to recover). When your fractured foot looks the same color as your non fractured foot when you shower, then swelling is usually done :) dr l.
Many possibilities. Swelling may last a long time following a foot or ankle injury. Elevation and use of compression socks or stockings may help to limit the swelling.
No actual number. Depending on the type of fracture, how long the cast was on, are you undergoing physical therapy. Could last a couple of weeks or months.