Enter the total battery capacity in amp hours and the energy usage in watts to calculate the total battery run time.

Battery Run Time Formula

The following equation is used to calculate the total run time of a battery.

T = 10 * a / w
  • Where T is the time in hours
  • a is the amp hours (battery capacity)
  • w is the power output/usage

To calculate the battery run time, divide the amp hours by the power output.