HomeElectronicsBattery Life Calculator

\u{1F50B} Battery Life Calculator

Estimate how long a battery will last based on its capacity (mAh) and the device's current draw (mA).

How to Calculate Battery Life

Battery life is calculated by dividing the battery capacity (in milliamp-hours, mAh) by the average current draw (in milliamps, mA). For example, a 3000 mAh battery powering a device that draws 150 mA will last approximately 20 hours.

In practice, batteries are not 100% efficient due to internal resistance, voltage regulation losses, and discharge characteristics. An efficiency factor of 80-90% provides a more realistic estimate. Lithium batteries are typically 85-95% efficient, while alkaline batteries may be 70-80% efficient at higher current draws.

AD PLACEMENT — IN-CONTENT (728×90)