Can you use the 12 Watt adapter from the Apple Wrist watch to charge an iPhone, or does the battery break? We explain how it works, whether it is harmful and whether charging the iPhone is faster with such an Apple Wrist watch charger.

Apple is supplying a 5 Watt power adapter with the iPhone, which makes the charging of the iPhone safe and steady. But sometimes you are a bit more in a hurry because you have to leave the door in about half an hour and are not able to recharge. Can you use the heavier Apple Wrist watch adapter of 10 Watt or 12 Watt?

  • Voltage and power
  • Is it safe?
  • 12 Watt
  • 5 Watt
  • Creep

Can you charge an iPhone with a 12 Watt Wrist watch adapter?

Voltage, current and power

First a small lesson in electricity. On each adapter you can see how much voltage (in Volt) it provides. It is also known for many devices which power (in Watts) it uses, for example with vacuum cleaners or electric kettles. With devices with a rechargeable battery such as the iPhone, it is known which kind of amperage (in Amps) is needed to charge the battery.

If you know two of the above values, you can calculate the missing value.

The power (in watts) can be calculated by multiplying the voltage with the current, in other words:

vermogen = spanning x stroomsterkte

If you connect an adapter with a too high voltage to a device, you can cause damage. A too low voltage is also not good, because then the charger can get very hot. Always make sure that the voltage that an adapter delivers is in order. With the iPhone and Apple Wrist watch chargers, a 5 Volt voltage is the standard, so that does not cause any problems.

The maximum current that a device can handle depends on the battery and the internal electronics of a device. The iPhone or Apple Wrist watch itself determines how much power is needed to charge the battery. The first iPhones could only be charged at a current of 1 ampere, 5 watt.

With newer models since the iPhone 6, it is possible to use higher amperage of 2.4 Amps. This is the principle behind fast charging ports in the car and fast charging with the iPhone. Your device is charged with 2.4 Amps and 5 Volts, so a total of 12 Watts. You can use the 12 Watt charger of the Apple Wrist watch but also the much heavier USB-C charger of your MacBook. Although it can handle a power of 29 Watt, the iPhone has built-in protection to ensure that charging is done at a safe speed.

iPhone with Apple Wrist watch adapter: is it safe?

If you charge an iPhone with an Apple Wrist watch adapter, you cannot do any damage. However, there is a difference in the speed with which the battery is charged. With an Apple Wrist watch adapter it goes much faster, but only if you have a relatively new iPhone. That is, from the iPhone 6.

This is how it works:

  • Older iPhone: these iPhones can only be charged with a current of 1 ampere. If you connect an Apple Wrist watch adapter, the device will simply be charged, but it will not be faster than usual.
  • You have a newer iPhone: these iPhones can handle higher currents. Charging is much faster with an iPad charger.

Examples of charging process

To make things even clearer, here are some examples:

  • You have a 1A charger and an iPhone that asks for 1A. The charger will charge at normal speed, eg 100 minutes.
  • You have a 2.1A charger and an iPhone that asks for 1A. The charger will deliver 1A and charging will also take 100 minutes.
  • You have a 2.1A charger and an iPhone that can handle fast charging. The charger will supply 2.1A and charging takes only 50 minutes.
  • You have a 1A charger and an Apple Wrist watch that supports fast charging. The charger will work, but charging takes a long time, eg 200 minutes.

Charge iPhone extra fast at 12 Watt

Can you charge an iPhone with a 12 Watt Wrist watch adapter?

Image source Apple .com

With car chargers and spare batteries you also often see a special (high-power) USB port for iPads. If you look closely, the higher amperage of 2.1A or 2.4A is also indicated. You can connect an iPhone to these USB chargers without worrying, for extra charge. If the iPhone cannot handle the higher amperage, there is nothing to worry about. He will draw less power from the charger, but there will be no damage. It is the iPhone that decides with which amperage the charging takes place, it is not the charger that imposes the higher amperage on the device.

Is the 5 Watt adapter suitable for every device?

Good to know: the 5 Watt adapter that you get with your iPhone is suitable for every iPhoneiPad and Apple Watch. This also applies to the 12 Watt Apple Wrist watch adapter. So if you’re looking for a replacement power adapter, then you better go for the larger 12 Watt version, since you can charge any mobile Apple device with it and can quickly charge.

How much creep power does an iPhone or Apple Wrist watch adapter use?

Another interesting question is how much it costs to keep your adapter plugged in. For the environment it is of course better to take out the adapter, but for your wallet it does not really matter. Official Apple chargers consume less than 0.2 watts when no iPhone or Apple Wrist watch is connected. On an annual basis, this means less than 1.8 kWh. If your energy company charges € 0.23 per kWh, you will not lose 50 cents per year. But if you add up all the appliances in the house, it can still hit quite a bit.

It is better to remove the adapter from the socket due to the risk of fire, even if the consumption is so low that hardly any heat will develop. Whether or not internal wear occurs when you use an adapter often, we can unfortunately not say.