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Online Calculator
Battery energy calculator (Wh)
Enter nominal voltage, capacity in Ah and percentage usable to estimate the stored energy.
The relationship Wh = V × Ah is an approximation based on nominal voltage. Actual energy depends on the discharge curve and battery type.
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Frequently asked questions
How do you calculate the Wh of a battery?
Wh ≈ V × Ah using the nominal voltage.
How many Wh are in a 12 V, 100 Ah battery?
Approximately 1,200 Wh nominal.
What does usable energy mean?
It is the nominal energy multiplied by the percentage of capacity you want to consider usable.
Is V × Ah exact?
It is a useful approximation; actual energy depends on the voltage and discharge curve.