Battery Run Time Calculator

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

Battery Run Time Definition

A battery run time is a total time in hours that a battery can sustain a certain power output.

Battery Run Time Example

The following is an example of how to calculate a total battery run time.

  1. First, determine the battery capacity. This is the total energy storage the battery can hold in amp hours. For this example we will say that value is 100 Ah.
  2. Next, determine the power output. This power output is also know as the usage rate and is measure in watts. We will say 50 watts for this problem.
  3. Finally, use the formula to calculate battery run time. 10 * 100 /50 = 20 hours.


What is battery run time?

Battery run time is the total amount of time a battery can sustain a certain power output. This run time will depends on several factors including discharge %, battery size, type of batter, and many more.

battery run time calculator
battery run time formula