Free Online Tool
Battery Life Calculator
Estimate runtime using battery capacity in mAh and load current in mA.
The result will appear here.
How to Use
- Enter battery capacity in mAh.
- Enter current draw in mA.
- Review estimated runtime in hours and days.
Examples
- Estimate runtime for 2000mAh and 100mA
- Check expected operating days for a low-power device
Calculation and Conversion Notes
Estimated runtime is calculated as `battery capacity(mAh) / current draw(mA)`. Actual runtime can vary with battery discharge characteristics, temperature, circuit efficiency, and load changes.
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