What formula is used?
mAh = Wh × 1000 ÷ V.
Battery energy to capacity
Wh to mAh Calculator
Convert watt-hours to milliamp-hours at a stated nominal battery voltage.
Interactive calculator
Wh to mAh Calculator
Result
5000.000 mAh
mAh = Wh × 1000 ÷ V
Live circuit diagram
Wh to mAh Calculator visualized in real time
Values update as you use the calculator.
Input
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Circuit setting
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Calculated output
Enter values to see the live result
Quick answers
Wh to mAh Calculator: quick answers
Get concise answers to the most common wh to mah calculator questions before reviewing the formulas, examples, and detailed guidance below.
Why is the second input needed?
Voltage is needed to translate energy into charge capacity.
Can I use decimal values?
Yes, enter positive decimal values in the displayed units.
Formula
Wh to mAh formulas
Choose the formula that matches the electrical system and known values.
Capacity
mAh = Wh × 1000 ÷ V
Use nominal battery voltage.
Energy
Wh = mAh × V ÷ 1000
Inverse relationship.
Amp-hours
Ah = Wh ÷ V
Then multiply Ah by 1000.
How to use
Calculate in five clear steps
Check every unit and use measured or nameplate values where possible.
- 1. Enter energy in Wh.
- 2. Enter nominal voltage.
- 3. Multiply Wh by 1000.
- 4. Divide by voltage.
- 5. Check chemistry, configuration, and usable capacity.
Worked examples
Practical calculation examples
Examples make the formula and its assumptions easier to verify.
18.5 Wh at 3.7 V
5,000 mAh
37 Wh at 3.7 V
10,000 mAh
24 Wh at 12 V
2,000 mAh
5 Wh at 5 V
1,000 mAh
77 Wh at 3.85 V
20,000 mAh
1,200 Wh at 12 V
100,000 mAh
Accuracy
Common mistakes and limitations
The result is only as reliable as the selected formula and input data.
Conversion library
Explore all 44 electrical calculators
Continue from the Wh to mAh Calculator to a dedicated conversion tool for watts, amps, volts, kW, kVA, energy, batteries, or circuit calculations. Each linked page includes its own formula, examples, and guidance.
FAQ
Wh to mAh questions
Direct answers to common calculation questions.
What formula is used?
mAh = Wh × 1000 ÷ V.
Why is the second input needed?
Voltage is needed to translate energy into charge capacity.
Can I use decimal values?
Yes, enter positive decimal values in the displayed units.
Why do units matter?
Incorrect prefixes or charge units can change a result by factors of 1000 or more.
Is this an exact conversion?
The arithmetic is exact for the stated ideal relationship and input assumptions.
Does battery efficiency matter?
Yes for real battery systems; nominal energy conversion does not include losses.
Can voltage change in a battery?
Yes. Battery voltage varies with chemistry, state of charge, load, and temperature.
Can this replace manufacturer data?
No. Use cell and pack specifications for final design.
Is electron-volt an SI unit?
It is a widely used non-SI energy unit accepted for atomic and particle physics.
Can I copy the result?
Yes, use the copy button.
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