Does Your Phone Fast Charge With a Laptop Charger?


If you’re reading this, you almost certainly own an electronic device that comes with its own charging cord, whether it’s a smartphone, laptop, or tablet. Is it really necessary to keep all those charging cables laying around, one for each gadget, if you possess many gadgets (as most of us do)?

Regardless of device, most charging cables and ports have matured to the point where they not only look the same but also perform the same basic purpose of charging the attached device.

The question then becomes: can you use your laptop charger to charge your phone quickly?

Does your phone fast charge with a laptop charger?

In a word – Yes. But before you get your hopes up, there are certain compatibility conditions that your phone and your laptop’s charger must meet. Here’s everything you need to know about fast charging your phone with your laptop charger.

Is it safe to use a Laptop charger with your phone?

Modern USB-C chargers and phones have built-in circuits that control energy flow and negotiate the charge rate. So it doesn’t really matter that your laptop charger is a mighty hunk built to charge devices that are many times the size of your phone. The phone will only take what it needs, nothing more.

This is also the reason why the laptop charger may heat up while charging the laptop, but not when charging the phone. In toto, it is safe to use a laptop charger with your phone, given, of course, that they are of the same USB standard.

The ubiquity of USB Type-C (and the one charger dream)

USB-C chargers have become so common in recent years that they are now included with practically every modern phone and laptop. The beauty of USB-C is that it can charge your phone quickly by increasing power flow in the first phase and then lowering the voltage in the second phase, when the majority of the battery has been charged, to avoid overheating.

Depending on the wattage capacity of your phone’s charger, you may be able to rapidly charge it. Laptop chargers, on the other hand, have a substantially higher power, which is understandable given the laptop’s larger size.

Despite the fact that the larger laptop charger has a higher charging capacity than your phone, both your phone and laptop chargers run at the same voltage, which is the USB-C standard that allows for cross charging.

The USB IF (Implementers Forum) defines four charging standards, each of which corresponds to one of four USB specifications:

  • USB 1.0 – 5V/0.5A (2.5W)
  • USB 2.0 – 5V/0.5A (2.5W)
  • USB 3.0 – 5V/0.9A (4.5W)
  • USB 3.1 – 5-20V/0.5-5A (100W)

USB Electricity Delivery, or USB-PD, is a fast charging standard that provides up to 20 volts and 100 watts of power. And this is where a phone’s compatibility with a laptop charger comes into play. You should be able to fast charge your phone using your laptop charger as long as it has a USB-PD connector.

Different levels of ‘fast charging’

Now, unless your phone can be charged quickly, there’s no reason to use a laptop charger for your phone. However, the definition of a fast charge varies depending on who you ask. Fast charging is referred to by different names by different phone makers. There’s One Plus’ Dash and Warp charging, Huawei’s Supercharge, Motorola’s Turbocharge, and so on.

Whatever you choose to call it, they’re all based on the USB-C standard connector, of which two primary fast charging standards exist:

USB-C PD (Power Delivery)

Previous USB specifications all specified a voltage level of 5 volts. The USB PD standard, on the other hand, is unique in that it provides several voltage levels depending on your needs – 5, 9, 15, and 20 – while supplying power up to 100 watts. With all of this extra electricity, your phone may easily fast charge if the phone and the laptop charger can create an operating protocol.

Quick charge

Qualcomm’s proprietary USB-C rapid charging protocol, Quick Charge, has grown in popularity as a result of the company’s chipsets’ broad use. Only version 4.0, however, is compatible with power supply. Most Snapdragon-powered devices support Qualcomm Quick Charge, which operates at up to 9V and 3 amps.

Trying to compare the multiple fast-charging standards in terms of exact speed would be splitting hairs. It’s safe to assume that phones and chargers that support the USB-C power delivery standard will produce between 18 and 60 watts of electricity, allowing you to charge your phone from 50% to 60% in less than half an hour.

When will your phone fast charge with a laptop charger?

There are a couple of conditions that must be satisfied before you can expect your laptop charger to fast charge your phone:

Fast charging protocols

Simply because one device has a USB-C connector does not indicate that its charger will work on the other. Both your laptop and your phone must have compatible charging protocols for charger compatibility to work.

If your laptop has a USB-C port, it should be able to deliver high-wattage power. Otherwise, charging a laptop with a conventional USB port would be very difficult. Because USB PD is also the standard used by your phone’s fast charging technology, the two are very certainly compatible.

Regulating input

At the same time, your phone’s battery and the charger should negotiate the amount of charge as well as the rate at which electricity is given. You won’t find a modern battery without an in-built controller that regulates the amount of charge that comes in. When combined with the fact that most chargers accept several voltage levels, the two determine how much input your phone can withstand without overheating.

Even if your phone doesn’t enable fast charging, this regulation guarantees that the charger automatically adjusts to the phone’s capabilities and charges at the usual 5V/1A rate.

If you’re obtaining one separately, it’s always a good idea to acquire at least two reliable chargers. This is due to the fact that there are numerous counterfeit USB-C chargers on the market that do not comply with the protocols and controlling input standards outlined previously. The importance of inspecting your USB-C PD charging cable cannot be overstated, despite the fact that they are a small and rapidly shrinking number. You don’t want your phone to be fried because of a bad cable that doesn’t interface with the phone to accept the voltage and current it requires.

Finally, as long as your laptop charger and your phone’s fast-charging protocols are compatible, fast charging your phone using the laptop charger should be simple.