Enter the Wh (watt-hours) and the voltage (volts) into the Calculator. The calculator will evaluate the mAh from Wh. 

mAh from Wh Formula

mAh = Wh*1000 / V

Variables:

  • mAH is the mAh from Wh (maH (milli-amp hours))
  • Wh is the Wh (watt-hours)
  • V is the voltage (volts)

To calculate mAh from Wh, multiply the watt-hours by 1000, then divide by the voltage.

How to Calculate mAh from Wh?

The following steps outline how to calculate the mAh from Wh.

  1. First, determine the Wh (watt-hours). 
  2. Next, determine the voltage (volts). 
  3. Next, gather the formula from above = mAh = Wh*1000 / V.
  4. Finally, calculate the mAh from Wh.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

Wh (watt-hours) = 675

voltage (volts) = 40

FAQs

What is mAh and why is it important?

mAh stands for milliampere-hour and is a unit that measures electric power over time. It’s commonly used to describe the energy capacity of a battery, indicating how long a battery can deliver a certain amount of current (milliamperes) before it needs recharging. This measurement is crucial for understanding how long a device can operate on a single charge.

How does voltage affect battery life?

Voltage (V) is a measure of electric potential, and it plays a significant role in battery life. Higher voltage can mean more power is delivered at once, potentially offering higher performance but possibly reducing the total available energy storage capacity (mAh) when calculated from watt-hours (Wh). The relationship between voltage and battery life is complex and depends on the device’s design and power requirements.

Can you convert Wh to mAh for any battery type?

Yes, the formula to convert Wh (watt-hours) to mAh (milliampere-hours) is universal and can be applied to any battery type, as long as you know the battery’s watt-hours (Wh) and its voltage (V). This conversion is useful for comparing the capacities of different batteries in a standard unit of measure.

Is it better to have a higher mAh rating?

A higher mAh rating indicates a larger energy capacity, meaning the battery can power a device for a longer period before needing a recharge. However, the ideal mAh rating depends on the device’s power requirements and how you use it. For high-power devices or those used for extended periods, a higher mAh rating is beneficial. But for devices with lower power consumption, a significantly higher mAh rating may not offer noticeable benefits and could contribute to a larger, heavier battery.