Although Apple makes a wide range of power adapters of different capacities, none of them – even the coolest 140W – will charge the iPhone faster than an 18-watt charger. This will not be allowed by the hardware of the smartphone, which corny does not support faster charging.
As a result, no matter what charger you take, get ready to spend at the outlet for an hour at best. What happens if you connect an iPhone to a MacBook? Will the laptop be able to charge a smartphone at high speed, and if not, what will be its limit? We will answer these and other questions in this article.
The iPhone can charge from the MacBook quite quickly, but it’s still not worth it to do this on an ongoing basis.
The need to recharge the iPhone from the MacBook can arise for various reasons. For example, when there are several devices that need to be charged. Then it is quite logical to connect the laptop to the outlet, and already from it to record discharged gadgets.
After all, if you have a MacBook Pro, then thanks to four connectors, you can simultaneously charge at least three devices: a smartphone, a tablet, and, say, headphones. But how fast will they charge?
iPhone charging speed from MacBook

The MacBook Pro’s USB port delivers 15W of output, allowing you to charge your iPhone even faster than a 5W power brick can.
The question is actually more complicated than it might seem at first glance. Because what matters is not so much the power adapter to which the MacBook is connected – Air or Pro – as the specifications of the USB-C connector to which the iPhone is connected.
We are talking about USB 3.0, USB 3.1 and USB 4.0 standards. And, interestingly, the same Mac computer can combine ports of different generations, so separating them by model and year of manufacture is not appropriate in this case.
Apple prefers not to share the power output of the USB ports of its laptops, and below it will become clear why this is correct, but it is known from open sources that the power delivered by the connectors of modern MacBooks varies from 4.5 to 15 watts:
- USB 3.0 – 4.5 – 5.5W
- USB BC 1.2 – 10.5W
- USB Type-C 1.2 – 15W
As a rule, all Macs are equipped with ports of different specifications. Take modern MacBook Pros for example: of the four USB connectors that Apple laptops carry, only two support a maximum output power of 15W , and the remaining two give out no more than 5.5W.
Even if you plug the laptop into the mains through the 140-watt power adapter that Apple released last year, the MacBook Pro’s iPhone charging speed will not increase.
The power of the USB connectors does not change depending on the type of computer. That is, stationary iMac, Mac mini or, say, Mac Studio charge external devices at the same speed as mobile models. Their maximum is 15 watts.
However, it happens that the iPad or iPhone does not charge from the MacBook : the charging icon is on, but the battery life is not replenished. This means that the external device does not have enough voltage. Why?
The reasons can be very different:
- Faulty USB port
- Resource-intensive tasks in progress
- Other devices are charging
- The main device requires too high voltage that the laptop cannot supply
Is it safe to charge an iPhone from a computer

When you charge an iPhone from a MacBook, it consumes the laptop’s battery life.
So if your Mac’s USB port puts out 15 watts, that’s great. Especially for iPhone. Yes, this is not the maximum indicator with which new Apple smartphones (18 W) can be charged , but still quite close to it. Thus, if you connect your iPhone to any modern Mac released after 2016, you can charge your smartphone within an hour and a half. The same applies to other devices, including the iPad.
Another thing is whether it is worth doing this at all, or, if you put the question in a different way, is it safe to charge an iPhone from a MacBook ? Well, frankly, there will definitely be little benefit from this.
Your laptop, that’s for sure. Indeed, at the time of charging, the laptop gives the smartphone the resource of its battery, which it receives from the power supply network. Losing energy, the MacBook is forced to continuously replenish it, which is directly a wear factor for it.
Understand correctly: you can recharge your iPhone from your MacBook once without any problems. This will not cause any significant harm to the smartphone or laptop. However, using a laptop as a branch for charging external devices on an ongoing basis is strongly discouraged, based purely on practical considerations. It is enough to translate the convenience of this charging method into collateral losses.
How much does it cost to replace a MacBook Pro battery ? About $230, if you take the old prices. And how much does a high-power power supply with multiple USB ports cost to charge 3-4 devices? Incomparably cheaper. It is much more profitable to buy this accessory and charge all devices directly, without using an intermediary.