How long should i keep an ankle support brace on a sprained ankle?

Until you feel : Comfortable walking without one. It also depends on what activities you're participating in. Sometimes, it will feel ok if you're on a flat surface, but if the surface is irregular (like grass) you may want to wear support for a while longer.

When limp gone: Bracing is used for comfort and stability. Use it until you are able to comfortably walk without the brace and not limp.

Used for support: If you have significant pain, you should rest the area. Ankle braces do help support the area by applying compression and restricting the range of motion. Consult with your physician as to whether or not and how long you should use an ankle brace for your type of injury. They are usually worn until you feel comfortable bearing weight on the area.