How many charges does a 10,000mAh power bank give your phone?
The number on a power bank is the capacity of the cells inside it, measured at their own 3.7 volts. Charging a phone means raising that to 5 volts or more, and some energy is lost as heat on the way. In practice about 60–70% of the rated capacity reaches your phone.
The simple maths
A 10,000mAh power bank delivers roughly 6,000–7,000mAh to your phone. Divide that by your phone’s battery size:
Most people don’t charge from empty. Topping up from 20% to 80% uses about 3,000mAh on a 5,000mAh phone, so a 10,000mAh bank gives you two of those top-ups.
Do you need 20,000mAh?
A 20,000mAh power bank roughly doubles the numbers above, but it is about twice the size and weight. For a day out or a long journey, 10,000mAh covers most phones; choose more only if you charge a tablet or several devices.
What else to look for
- Fast charging. 22.5W models refill a phone that supports fast charging much quicker; other phones still charge at their normal speed.
- Built-in cables. Several WisdomUp power banks carry their own cables, so you never leave the cable at home.
- Flying. A 10,000mAh bank holds about 37Wh, under the 100Wh limit airlines generally allow — but power banks must go in your hand luggage, never in checked bags.
WisdomUp power banks and today’s prices
See all power banks, or read how to charge fast and safely at home and in the car.
