Battery Life Calculator

Estimate battery runtime from battery capacity (mAh/Wh) and device power consumption.

mAh
mA
Battery Runtime
—hours
Minutes—
Watt-hours (3.7V)—

Battery Runtime Formula

Runtime (hours) = Battery Capacity (mAh) ÷ Device Draw (mA). Real-world runtime is typically 80-90% of calculated due to efficiency losses.