An inflatable sport ball, such as a basketball, a football, a soccer ball, a volleyball or a playground ball, is provided with a self-contained inflation mechanism, or multiple self-contained inflation mechanisms, for inflating or adding pressure to the ball and a pressure sensor and pressure indicator to indicate the internal pressure of the ball. The inflation mechanism is a pump which is positioned and retained inside of the ball and which is operable from outside of the ball to pump ambient air into the ball. The pressure indicator provides a numerical indication of the internal pressure of the ball as measured or determined by the pressure sensor.