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© 2026 WattQuick. All calculators are estimates—for planning only, not professional engineering advice.

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Battery

Battery Percentage

Find remaining charge as a percentage of full capacity.

Current chargemAh

Full capacitymAh

Charge level

Enter current and full capacity

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About Battery Percentage

How battery percentage works

Percentage = (current charge ÷ full capacity) × 100. Use the same unit for both values—milliamp-hours (mAh) or amp-hours (Ah).

Why estimates differ from your phone

Devices estimate state-of-charge with voltage curves and usage history. This calculator gives a simple linear ratio useful for pack planning and quick checks.

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