Battery Life Calculator
Enter battery capacity, load current, and an efficiency factor to instantly calculate estimated battery runtime in hours and minutes.
Battery Parameters
Total rated capacity of the battery pack.
Average current drawn by the device.
Estimated Battery Life
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Formula used:
t = Ceff / I where
Ceff = Cusable × (C1h / I)n−1
Simplified for constant load: t (h) = Cusable / In × C1hn−1
C1h is the 1-hour discharge rate; for a pure Peukert estimate: t = (Cusable / I)n hours.
Simplified for constant load: t (h) = Cusable / In × C1hn−1
C1h is the 1-hour discharge rate; for a pure Peukert estimate: t = (Cusable / I)n hours.
Summary
Enter battery capacity, load current, and an efficiency factor to instantly calculate estimated battery runtime in hours and minutes.
How it works
- Enter the battery capacity in milliamp-hours (mAh).
- Enter the load current draw in milliamps (mA).
- Optionally adjust the Peukert exponent (default 1.05 for Li-ion).
- Optionally set a derating factor (%) to account for aging or temperature.
- The tool applies the Peukert equation and displays runtime in hours and minutes.
Use cases
- Estimate how long an IoT sensor will run on a coin cell battery.
- Plan field deployments for wireless devices with known current draw.
- Compare battery packs for RC vehicles or drones.
- Verify battery sizing for emergency backup power systems.
- Evaluate power budgets for wearable electronics prototypes.
- Determine recharge frequency for portable medical devices.
Frequently Asked Questions
Last updated: 2026-06-10 ·
Reviewed by Nham Vu