Electronics

Battery Life Calculator

How long will your battery last? Enter capacity and load — current draw or wattage — and get runtime with a realistic discharge factor.

Runtime = (Capacity × Depth-of-discharge) ÷ Load current

🔌 Realistic factors

Lead-acid and alkaline batteries can't be fully drained — we account for it.

📈 mA or watts

Enter current directly, or convert wattage using your battery voltage.

🔁 Any battery size

From tiny Li-Po packs to large 12 V deep-cycle batteries.

⚡ Instant results

Runtime in hours, minutes and full days where applicable.

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