mAh to Wh Calculator
Convert battery milliamp-hours to watt-hours instantly. Enter battery mAh and voltage to find watt-hours and compare battery energy across Li-ion, LiFePO4, and LiPo chemistries.
mAh to Wh Conversion Tool
Enter battery milliamp-hours and cell voltage to instantly convert mAh to watt-hours. Quick-select chemistry to auto-fill common cell voltages.
Milliamp-Hours to Watt-Hours Converter
This tool converts any mAh battery value to watt-hours using the formula Wh = mAh × V ÷ 1000.
Conversion Results
These results show watt-hours, kilowatt-hours, the equivalent Ah value, and the formula applied to the entered battery.
Educational Estimates Only: Results are based on nominal cell voltage. Real battery energy may vary due to temperature, charge level, chemistry-specific discharge curves, and manufacturer tolerances. Verify with datasheets for critical use.
mAh to Wh Basics
Converting mAh to Wh requires battery voltage. The result shows actual energy rather than charge alone, which is more useful for comparing batteries.
Milliamp-hours measure electrical charge, while watt-hours measure actual stored energy. Two batteries with the same mAh can store different amounts of energy if they have different voltages, so converting to watt-hours is the better way to compare them.
For example, 3000mAh at 3.7V equals 11.1Wh, 10000mAh at 3.7V equals 37Wh, and 20000mAh at 3.7V equals 74Wh. These examples use 3.7V, which is the common nominal cell voltage for Li-ion and LiPo batteries. LiFePO4 cells typically use 3.2V, which gives a slightly lower watt-hour result for the same mAh.
Dividing by 1000 in the formula converts milliamp-hours into amp-hours first, and multiplying by voltage then converts amp-hours into watt-hours. This makes the result directly comparable across batteries with different voltages.
Conversion formula
- Wh = mAh × V ÷ 1000.
- Use 3.7V for Li-ion.
- Use 3.2V for LiFePO4.
- Use 3.7V for LiPo.
Examples
- 3000mAh @ 3.7V = 11.1Wh.
- 10000mAh @ 3.7V = 37Wh.
- 20000mAh @ 3.7V = 74Wh.
Why convert mAh to Wh?
Wh measures actual energy, which is better for comparing battery capacity across different voltages. mAh alone does not tell you how much usable energy a battery stores.
What is 10000mAh in Wh?
At 3.7V, 10000mAh equals 37Wh. At 3.2V, the same 10000mAh equals 32Wh, so voltage matters when comparing battery energy.
Frequently Asked Questions
These are common questions about mAh to Wh conversion, cell voltage, and how to compare battery energy across chemistries.
Why convert mAh to Wh?
Wh measures actual energy, which is better for comparing battery capacity across voltages.
What is 10000mAh in Wh?
At 3.7V, 10000mAh equals 37Wh.
What is the mAh to Wh formula?
Wh = mAh × V ÷ 1000. Multiply milliamp-hours by voltage and divide by 1000.
What voltage should I use for Li-ion?
Use 3.7V as the common nominal cell voltage for Li-ion batteries.
What voltage should I use for LiFePO4?
Use 3.2V as the nominal cell voltage for LiFePO4 batteries.
What voltage should I use for LiPo?
Use 3.7V as the common nominal cell voltage for LiPo batteries.
What is 3000mAh in Wh?
At 3.7V, 3000mAh equals 11.1Wh.
What is 20000mAh in Wh?
At 3.7V, 20000mAh equals 74Wh.
Is mAh the same as Wh?
No. mAh measures charge, while Wh measures energy. You need voltage to convert between them.
Can I use this for power bank ratings?
Yes. Power banks often list mAh at a cell voltage such as 3.7V. Use this formula to find the actual watt-hour energy stored.
Compare Battery Energy Better
Use this calculator to convert mAh to watt-hours, then compare related tools to estimate runtime and compare battery energy more accurately.
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