battery tool
Ah to Wh Calculator
Convert amp-hours into stored watt-hours.
This is nominal stored energy before application-specific DoD or conversion losses.
Stored energy
12000 Wh
Wh = volts × amp-hours.
Battery energy conversion
Convert amp-hours to watt-hours
Amp-hours describe charge capacity. Watt-hours describe nominal stored energy. Voltage connects the two measurements, so the same Ah rating can represent different energy at different system voltages.
Formula
Wh = Ah × V
Worked examples
12 V system: 100 Ah × 12 V = 1,200 Wh.
24 V system: 100 Ah × 24 V = 2,400 Wh. The Ah rating is the same, but the nominal energy is different.
Reference table
| Capacity | Voltage | Nominal energy |
|---|---|---|
| 100 Ah | 12 V | 1200 Wh |
| 100 Ah | 24 V | 2400 Wh |
| 100 Ah | 48 V | 4800 Wh |
These are nominal values before depth-of-discharge and efficiency limits.
Frequently asked questions
Why is voltage required for Ah to Wh?
Amp-hours measure charge, not energy by themselves. Voltage is required because watt-hours equal amp-hours multiplied by volts.
Are two batteries with the same Ah rating equivalent?
Not necessarily. A 100 Ah battery at 12 V stores a different nominal amount of energy than a 100 Ah battery at 24 V or 48 V.
Does this include depth of discharge?
No. This is a nominal conversion. Depth of discharge, efficiency, and chemistry are separate application assumptions.
What is the formula?
Wh = Ah × V.
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.