The majority of power bank manufacturers exaggerate how frequently their products can recharge particular gadgets.

But do they? It turns out that you can compute this yourself without relying on other power bank makers to trick you. Just a little bit of math is all that is required. You can become an authority on power banks with a few calculations.

You may be asking how you are supposed to generate these numbers.

### How To Calculate How Many Times Your Power Bank Can Charge

Though I think we can all agree that math isn’t the most enjoyable topic, you may disagree. It’s crucial to understand how manufacturers determine how many times their power banks can recharge specific devices, such as iPhones or Samsung smartphones, even though you might not enjoy the topic.

The secret recipe is as follows:

1. The number of charges for the device equals the power bank’s labelled capacity multiplied by 3.7, the power bank’s output voltage multiplied by 0.85, and the drive’s battery capacity.

Please take note that if you are using a USB-C PD port to charge your smartphone, you cannot use this formula. This is due to the output altering based on the input requirements of the phone. It’s setup differently from other power banks. However, 5V can be used as a guide.

### How Many mAh to Charge an iPhone?

#### For the iPhone X

To calculate how many mAh it would take to charge your iPhone, apply a formula. To achieve this, you must ascertain the mAh capacity of your battery bank. A full-size power bank designed for phone charging would have a capacity of roughly 20,000 mAh. The second thing you must do is determine the battery voltage of your iPhone Xs, which is 3.7 volts.

Once you know this, you must determine the power bank’s output voltage, which can be found on the label. Once you have this, you must know the energy efficiency of your power bank, which is typically around 85% since 15% of the energy used by power banks is lost to heat. The final number you’ll need to punch in is the 2,716 mAh of the iPhone X’s battery.

(20,000x3.7 / 5) x 0.85 / 2,716 mAh = 4.6 recharges

A 2,716mAh battery powers the iPhone X. Using the formula, a 20,000 mAh power bank may provide up to 4.6 recharges. Naturally, older versions will recharge far more slowly than newer models.

#### For an iPhone 11

(20,000x3.79 / 5) x 0.85 / 3,110 mAh = 4.14 recharges

A 3,110 mAh battery powers the iPhone 11. Using the formula, a 20,000 mAh power bank may provide up to 4.14 recharges. Naturally, older versions will recharge far more slowly than newer models.

#### For An iPhone 12

An iPhone 12 can be charged using a 20000mAh power bank four and a half times.

(20000 * 3.83 / 5) * .85 / 2,815 = 4.6

An iPhone 12 can be charged with a 25000mAh power bank almost six times!

(25000 * 3.83 / 5) * .85 / 2,815 = 5.8

An iPhone 12 may receive two charges from a 10000mah power bank.

(10000 * 3.83 / 5) * .85 / 2,815 = 2.3

#### For an iPhone 13

A 20000mah power bank can almost four times the amount of an iPhone 13!

(20000 * 3.7 / 5) * .85 / 3,227 = 3.9

A 25000mAh power bank can roughly 5 times as many times as an iPhone 13

(25000 * 3.7 / 5) * .85 / 3,227 = 4.9

An iPhone 13 can practically be charged twice using a 10000mah power bank.

(10000 * 3.7 / 5) * .85 / 3,227 = 1.9

### How Many mAh to Charge an Android?

#### For an S 10

A 20000mah power bank can nearly charge a Galaxy S10 four times.

(20000 * 3.85 / 5) * .85 / 3,400 = 3.85

A 25000 power bank can nearly recharge a Galaxy S10 five times!

(25000 * 3.85 / 5) * .85 / 3,400 = 4.8

With a 10000mah power bank, a galaxy S10 can still be charged practically twice.

(10000* 3.85 / 5) * .85 / 3,400 = 1.9

#### For the Galaxy S11

(20,000x3.85 / 5) x 0.85 / 4,500 mAh = 2.9 recharges

A 4,500 mAh battery powers the Galaxy s11. Using the formula, a 20,000 mAh power bank may provide up to 2.9 recharges. Naturally, older versions will recharge far more slowly than newer models.

#### For an S 20

A 20000mah power bank can charge a Galaxy S20 three times.

(20000 * 3.85 / 5) * .85 / 4,000 = 3.2

A 25000 power bank can recharge a Galaxy S20 four times.

(25000 * 3.85 / 5) * .85 / 4,000 = 4.1

Your S20 can be nearly double-charged using a 10000mah power bank.

(10000 * 3.85 / 5) * .85 / 4,000 = 1.6

#### For An S 21

A 20000mah power bank can charge a Galaxy S21 three times!

(20000 * 3.85 / 5) * .85 / 4,000 = 3.2

A powerful 25000mah power bank can recharge a Galaxy S21 more than four times.

(25000 * 3.85 / 5) * .85 / 4,000 = 4.1

A 10000mah power bank can nearly double the amount of times the Samsung Galaxy S21 can be charged.

(10000 * 3.85 / 5) * .85 / 4,000 = 1.6

#### For an S 22

An S22 may be charged using a 20000mah power bank more than three times.

(20000 * 3.85 / 5) * .85 / 3700 = 3.5

The 25000mah power banks have a higher capacity and can charge an S22 four times!

(25000 * 3.85 / 5) * .85 / 3700 = 4.2

With the cost-effective 10000mah power banks, an S22 may be charged almost twice as much.

(10000 * 3.85 / 5) * .85 / 3700 = 1.8

As a general rule, divide the mAh of your power bank by the mAh of the battery in your device.

Although it won’t be as exact as using the method, you may always utilise the simpler concept above if you’re having trouble understanding the formula.

### What Do The Numbers Mean?

You might or might not comprehend everything at this stage.

An explanation of what everything signifies is provided below:

3.7 The 3.7 is the first multiple. Although a battery cell can have a variety of voltage values, the average voltage is 3.7 volts. Manganese-containing Li-ion batteries typically operate at 3.7 volts. Cobalt-containing Li-ion batteries typically operate at 3.6 volts.

5 The number you multiply by after that is 5. The normal power bank’s average voltage output is 5, which is the number. The output varies between different power banks.

A power bank that allows fast charging will differ from one that simply supports USB, for instance. If you already own a power bank, the description for it should say as much on the packaging. The output of your power bank can be substituted for the number 5 in the equation if you are able to determine what it is.

0.85 The first three digits enclosed in brackets in the equation are multiplied by 0.85. In order to provide 100% efficiency to the device, all power banks must first transfer energy, which causes some of their efficiency to be lost through heat.

Additionally, they lose some energy due to the light.

Due to the wasted voltage, the average efficiency sent directly to your device is approximately 85%, which is why you use 0.85 in the equation.

Keep in mind that this varies amongst chargers and that it is an average. It is untrue if any manufacturers claim that their power banks are 100% efficient.

### Specific Recharge Times

In case you don’t have time to perform the arithmetic, below are some precise recharge timeframes. The two common capacities I’ll be using are 10,000 mAh and 20,000 mAh.

So an iPhone may be entirely charged using a 10,000 mAh power bank that has been fully charged:

- iPhone 7: (10,000 3.7 / 5) x 0.85 / 1960 mAh = 3.2 recharges
- iPhone 8: (10,000 3.7 / 5) x 0.85 / 1,821 mAh = 3.4 recharges
- iPhone X: (10,000 3.7 / 5) x 0.85 / 2716 mAh = 2.3 recharges
- iPhone 11: (20,000 3.79 / 5) x 0.85 / 3,110 mAh = 2.7 recharges
- Galaxy S8: (10,000 3.7 / 5) x 0.85 / 3000 mAh = 2 recharges
- Galaxy S9: (10,000 3.7 / 5) x 0.85 / 3000 mAh = 2 recharges
- Galaxy S11: (20,000 3.85 / 5) x 0.85 / 4,500 mAh = 1.45 recharges

So an iPhone may be entirely charged using a 20,000 mAh power bank that has been fully charged:

- iPhone 7: (20,000 3.7 / 5) x 0.85 / 1960 mAh = 6.4 recharges
- iPhone 8: (20,000 3.7 / 5) x 0.85 / 1,821 mAh = 6.8 recharges
- iPhone X: (20,000 3.7 / 5) x 0.85 / 2716 mAh = 4.6 recharges
- iPhone 11: (20,000 3.79 / 5) x 0.85 / 3,110 mAh = 4.14 recharges
- Galaxy S8: (20,000 3.7 / 5) x 0.85 / 3000 mAh = 4 recharges
- Galaxy S9: (20,000 3.7 / 5) x 0.85 / 3000 mAh = 4 recharges
- Galaxy S11: (20,000 3.85 / 5) x 0.85 / 4,500 mAh = 2.9 recharges

Note: These illustrations also apply to gadgets like tablets and cameras.

The 20,000 mAh power bank charges the gadgets twice as quickly as the 10,000 mAh power bank, as you can see. You will require a power bank with a huge battery capacity if you own a new device that uses a large battery.

### Factors that Affect How Many Time Your Can Recharge

To charge your gadget as frequently as possible, you need to be aware of the elements that effect recharges before finding out how many times it may be charged.

1. Utilizing a device If you are viewing a movie on Netflix or another form of entertainment on your device. Your smartphone will look to have never been charged.

The more you use your gadget while it’s plugged in to the charger, the more power it will lose. In essence, you are charging the battery quickly while simultaneously discharging it.

2. Not utilising a device The amount of use you give it could be another factor affecting how long it takes to recharge. For instance, while it was charging, you left your phone on aeroplane mode.

If this is your approach when charging your device, you re going to get a lot more recharges out of the power bank. This is because the device isn t using much battery power while it s being charged.

3. Age of the Battery When using lithium polymer batteries, you need to know that the capacity of the battery also reduces with age.

For example, a 10,000 mAh power bank you bought today may only have a capacity of 8500 mAh in a year s time.

You can slow this process down by storing your power bank in the correct place. A battery that s stored at high temperatures (such as 30 degrees) is going to deteriorate a lot faster than a power bank stored at a cooler temperature.

This doesn t mean that you should store your battery in the freezer! Just keep it s in a cool dry environment or keep it directly away from the sun. This is going to prolong the capacity of your power bank.

4. Efficiency of Your Battery You also need to know that your device may have lost a few capacities over time. If your device is fairly old, (let s say over 1 year) this would be the case.

When you charge your device to 100%, you may think that your device actually has 100% charge. In reality, your device is actually charged to 80% or 90% but it ll appear as if it s charged to 100%. Again, this is due to the condition and the age of the battery.