To convert milliamp-hours to amp-hours, multiply by 0.001. That factor is the whole relationship: both units measure the total quantity of electricity, including battery capacity, so the conversion is a proportion with no offset and no substance-specific constant.
The milliamp-hour is how every phone, laptop and power-bank battery is rated. One mAh is 3.6 coulombs, because an hour is 3,600 seconds. Amp-hours rate car, leisure and solar batteries. A 100 Ah battery can in principle deliver one amp for a hundred hours.
Milliamp-hours are charge, not energy. Two batteries both rated 3,000 mAh store different amounts of energy if their voltages differ, which is why power banks advertise mAh at cell voltage and deliver less at USB voltage. Below the calculator there is a step table for the values people look up most, and a second table putting real the total quantity of electricity, including battery capacity figures into amp-hours so the number you get has something to be compared against.
The formula
milliamp-hours- The amount you are converting, in milliamp-hours
0.001- The exact number of amp-hours in one milliamp-hour
amp-hours- The converted result
How it works, step by step
- Enter the value in milliamp-hours.
- It is multiplied by 0.001, the exact factor between the two units.
- The answer is shown in amp-hours, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
AA alkaline cell: 2500 mAh in amp-hours
At 2500 mAh (aa alkaline cell), the same quantity in amp-hours is 2500 × 0.001 = 2.5 Ah. One milliamp-hour is 0.001 amp-hours, so the numbers shrink as expected.
Car battery, 60 Ah: 6e+04 mAh in amp-hours
Car battery, 60 Ah comes to about 6e+04 mAh. Multiplying by the factor: 6e+04 × 0.001 = 60 Ah. Dividing the answer back by 0.001 returns the figure you started with, which is the quickest way to check you have the factor the right way up.
How to read your score
Frequently asked questions
How many amp-hours are in one milliamp-hour?
Exactly 0.001. Every figure on this page is that one number multiplied by your input, so the only rounding is at the display step.
What is the formula to convert milliamp-hours to amp-hours?
amp-hours = milliamp-hours × 0.001. Reversed, milliamp-hours = amp-hours ÷ 0.001, which is the same as multiplying by 1000.
Which is the bigger unit, the milliamp-hour or the amp-hour?
The amp-hour. One milliamp-hour is only 0.001 of a amp-hour, so it takes 1000 milliamp-hours to make one amp-hour.
What does this quantity actually measure?
Both units measure the total quantity of electricity, including battery capacity. That is why a single factor is enough: there is no temperature offset and no material property involved, unlike conversions that cross between different quantities.
What is a milliamp-hour?
The milliamp-hour is how every phone, laptop and power-bank battery is rated. One mAh is 3.6 coulombs, because an hour is 3,600 seconds.
What is a amp-hour?
Amp-hours rate car, leisure and solar batteries. A 100 Ah battery can in principle deliver one amp for a hundred hours.
Why does my answer differ from another converter?
Almost always because the other tool rounded the factor before multiplying. This page keeps full double precision through the calculation and rounds only for display, and it prints the factor it used so you can see where any difference came from.
Milliamp-Hours to amp-hours reference tables
| Milliamp-Hours | Amp-Hours |
|---|---|
| 0.5 mAh | 0.0005 Ah |
| 1 mAh | 0.001 Ah |
| 2 mAh | 0.002 Ah |
| 3 mAh | 0.003 Ah |
| 5 mAh | 0.005 Ah |
| 10 mAh | 0.01 Ah |
| 20 mAh | 0.02 Ah |
| 25 mAh | 0.025 Ah |
| 50 mAh | 0.05 Ah |
| 75 mAh | 0.075 Ah |
| 100 mAh | 0.1 Ah |
| 250 mAh | 0.25 Ah |
| 500 mAh | 0.5 Ah |
| 1000 mAh | 1 Ah |
| 5000 mAh | 5 Ah |
Exact factor: 1 milliamp-hour = 0.001 amp-hours.
| Quantity | mAh | Ah |
|---|---|---|
| AA alkaline cell | 2500 mAh | 2.5 Ah |
| Phone battery, 4000 mAh | 4000 mAh | 4 Ah |
| Laptop battery, 60 Wh at 11.1 V | 5405 mAh | 5.405 Ah |
| Car battery, 60 Ah | 6e+04 mAh | 60 Ah |
| Camera flash capacitor | 0.01389 mAh | 1.389e-05 Ah |
| Lightning strike | 4.167 mAh | 0.004167 Ah |
Published reference values, converted with the same factor this page uses.