Battery Life Calculator
How to estimate battery life
- Enter the battery capacity in mAh.
- Enter the current your device draws when active, the share of time it is active and its sleep current.
- Keep 85% usable capacity or change it to see the running time.
Frequently asked questions
Why not use the full capacity?
Batteries rarely deliver their full rating in practice: the capacity drops with high current, cold and age, and devices stop before the battery is completely empty.
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