Foot pain in the "ball of your foot," that area between your arch and the toes, is generally called metatarsalgia. The pain usually centers on one or more of the five bones in the middle portion of the foot.

Causes
Foot pain is sometimes caused by a callus that forms on the bottom of your foot. A callus is a build-up of skin that forms in response to excessive pressure over the bone. Normally, a callus is not painful, but the build-up of skin can increase the pressure and eventually make walking difficult.

Shoes that don’t fit properly because they are too tight or too loose can cause foot pain. Tight shoes squeeze the foot and increase pressure; loose shoes let the foot slide and rub, creating friction.

Symptoms
Pain on the underside of the foot may indicate a torn ligament or inflammation of the joint.

Treatment
Most of the time, practical measures can help ease foot pain. Your doctor may recommend that you use a shoe insert (orthosis) as a kind of shock absorber, or that you wear a different kind of shoe. Sometimes, simply buying shoes that fit properly can solve the problem. Shoes should have a wide toe box that doesn’t cramp your foot. Heels should never be higher than 2-1/4" high. Soaking your feet to soften calluses, then removing some of the dead skin with a pumice stone or callus file will also ease pressure.  Occasionally, surgery may be necessary to remove a bony prominence or correct a deformity.