Battery Life Calculator

Enter value and click on calculate. Result will be displayed.
Capacity Rating of Battery :
Milli Amp Hours
Consumption of device:
Milli Amps
Battery Life:
Hours

A Battery Life Calculator is a tool (either an online tool, software, or formula) used to estimate how long a battery will last based on a few key parameters. It helps you figure out the runtime of a device powered by a battery, often for electronics, IoT devices, or larger battery-powered systems.

The calculation usually depends on:

Battery Capacity: Measured in milliampere-hours (mAh) or ampere-hours (Ah). This tells you how much charge the battery can store.
Device Power Consumption: The current the device draws, usually in milliamps (mA) or watts (W).
Voltage (sometimes): Especially when using watt-hours for capacity.
Efficiency: If there are power losses in the system.
A simple formula for battery life:


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For example, a 5000mAh battery powering a device that draws 500mA would last:


If you're using watts and watt-hours:

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Some calculators also account for things like standby time, intermittent usage, or different discharge rates.