Maximum capacity of portable power bank

Technically, there is no maximum mAh capacity for a power bank. Power banks are available in a wide range of capacities, from as little as 1000 mAh to as much as 50,000 mAh or more.

Again, for a standard laptop, a 20,000 mAh power bank with a compatible USB-C PD port is the minimum requirement. You can also look at 30,000 mAh or 50,000 mAh power banks. On the other hand, if you are planning to go camping/hiking, it's best to rely on a heavy-duty power bank.

Fortunately, there's an easy equation to figure out the size you need. Let's say that your power bank has 5,000 mAh. You need to multiply the capacity by the volt rating to get the mWh: the megawatt-hour rating.

For example, if you have the Google Pixel 8a, the Miisso 6,000 mAh portable charger should be good for backup. However, if you have a smartphone with a large battery or a laptop, opting for a heavy-duty power bank is wise. However, it's not as simple as buying a 5,000 mAh power bank to charge a 5,000 mAh smartphone. Life should be that simple, no?

Everyone's needs are different, but if you only occasionally need to charge a mobile phone, smartphone or a watch, a power bank with at least 10,000 mAh or 22.5 watts will meet your needs. A 30 watt, 10,000 mAh power bank is another option that meets many people's needs.

Simply put, capacity matters. It determines how many times you can use your power bank to charge your devices before the power bank itself needs to recharge. So you want a power bank with fast, efficient charging technology. Capacity is measured in milliampere hours (mAh).