battery tool
Wh to Ah Calculator
Convert watt-hours into amp-hours at a selected voltage.
This is a nominal conversion and does not account for DoD, efficiency, or battery chemistry.
Battery capacity
10 Ah
Ah = watt-hours ÷ volts.
Battery capacity conversion
Convert watt-hours to amp-hours
Watt-hours tell you how much nominal energy is represented. Amp-hours describe charge capacity at a particular voltage. Voltage is essential because the same Wh value maps to different Ah values at 12 V, 24 V, or 48 V.
Formula
Ah = Wh ÷ V
Worked examples
12 V: 1,200 Wh ÷ 12 V = 100 Ah.
24 V: 2,400 Wh ÷ 24 V = 100 Ah. The energy and voltage both doubled, so the Ah result stayed the same.
Reference table
| Energy | Voltage | Equivalent capacity |
|---|---|---|
| 2,400 Wh | 12 V | 200.0 Ah |
| 2,400 Wh | 24 V | 100.0 Ah |
| 2,400 Wh | 48 V | 50.0 Ah |
This conversion does not account for chemistry, DoD, or conversion efficiency.
Frequently asked questions
Why does voltage matter when converting Wh to Ah?
Amp-hours are charge capacity, while watt-hours are energy. Dividing Wh by voltage gives the corresponding Ah at that voltage.
What is the formula?
Ah = Wh ÷ V.
Does the result show usable battery capacity?
No. It is a nominal conversion and does not subtract depth-of-discharge or efficiency losses.
How does this relate to Ah to Wh?
The two calculators are inverse conversions: Ah to Wh multiplies by voltage, while Wh to Ah divides by voltage.
Important assumptions
This is a planning estimate, not a guarantee of performance. Real equipment varies with temperature, age, power quality, duty cycle, wiring, and manufacturer specifications.