mAh to Wh Calculator

How to Convert mAh to Wh Using Our Calculator

Our custom-made calculator is designed to convert charge capacity specified in mAh to energy specified in Wh. Here’s how to use our conversion calculator:

1. Input the capacity in mAh
2. Choose the desired voltage (if you’re calculating for a power bank, use 3.7V as the base value)
3. Click the red “Calculate” button
4. See the result
5. Click the “Reset” button to run another calculation

mAh to Wh Conversion Formula

If you want to do the conversion by hand, here’s the formula behind our Wh calculator:

Wh = mAh × V / 1000

mAh stands for milliamp-hour and it’s the unit of electric charge and commonly used to express the capacity of the small batteries. mAh specifies the total amount of charge passing through a point in a certain period of time. A battery with a higher mAh value will power a system for a longer time. It is typically used to specify and describe the total amount of energy retained by a battery.

Wh stands for Watt-hour and it’s another commonly used and accurate unit for comparing the capacity of batteries that have different voltages. Wh is calculated from the voltage (V) provided by a battery, multiplied by the current (amps) supplied by a battery for a certain time (usually in hours). Generally, we use mAh for cells and batteries, whereas watt-hours for energy storage systems.

mAH does not indicate the power capacity of a battery as two batteries with the same mAh value may deliver a different amount of energy. We must consider another variable, the Volt, for calculating the power capacity denoted by Wh. Volt refers to the difference in the electric potential between the positive and negative terminals of a battery. It is the force required to overcome the resistance and move the electrons to make the battery work.

How Many Volts Do Power Banks Have?

The voltage of a power bank depends upon the battery cells used and can fluctuate between brands and models. However, generally speaking, the battery cells in power banks are either Li-Poly or Li-Ion, both of which are 3.7 Volts.

It’s also worth mentioning the fact that if the voltage is smaller than the voltage of your device, charging cannot occur. This is why all power banks come with a step-up voltage converter to produce the 5 Volts required for charging an external device.

New power banks are now available in the market, supporting fast charging and often delivering up to 9 Volts. Most of the power banks have battery cells internally connected in series to achieve the required voltage. For example, if a power bank has four Li-ion cells connected in series, it will have an overall voltage of 14.8 Volts.

A lot of people don’t know if they’re allowed to take power banks on planes or not. It is very important to know the Wh value of your power bank to comply with the rules and regulations referring to power banks and batteries in the travel industry. For example, you cannot take a battery exceeding 100Wh on planes.

Common Power Bank Capacities From mAh to Wh

Here are some very common power bank mAh capacities and their values in Wh:

• 5000mAh = 19Wh
• 10000mAh = 37Wh
• 15000mAh = 56Wh
• 20000mAh = 74Wh
• 20000mAh = 74Wh
• 30000mAh = 111Wh
• 50000mAh = 185Wh

Common Power Bank Capacities From Wh to mAh

If you want to know the capacity of your battery or portable charger the other way around, here are some common values: 

• 10Wh = 2702mAh
• 20Wh = 5405mAh
• 50Wh = 13515mAh
• 100Wh = 27027mAh
• 150Wh = 40540mAh
• 160Wh = 43243mAh
• 200Wh = 54054mAh

Please bear in mind that all of these examples are calculated based on the average 3.7V value for standard Li-ion batteries. If you have batteries that have different voltages, you’ll need to redo the calculations using the correct voltage value. These examples work for most power banks, smartphones, and similar devices which generally come with 3.7V batteries. 

Hopefully, now you understand better the relation between mAh and Wh and can confidently make the conversion. In case you have any questions regarding the formula or our calculator, please drop us a line via the contact form.