Can a USB C Phone Charger Charge a Laptop? Full Guide

Almost all phones, tablets, laptops, and desktop computers have USB-C ports. That raises a common question: can a USB C phone charger charge a laptop with the same port? This guide answers the question in great detail and even highlights how you can safely charge a laptop with a USB-C phone charger, what to look out for, and whether your regular phone charger is up to the task.

alt: Can a usb c phone charger charge a laptop

Can You Charge a Laptop with a USB‑C Phone Charger?

Can a USB‑C phone charger charge a laptop?  It depends on four main factors: the charger’s wattage, the USB‑C cable you’re using, whether your laptop supports USB Power Delivery (USB‑PD), and if the laptop’s USB‑C port supports charging, not just data transfer.

USB‑C Port Compatibility

Not all USB‑C ports on laptops can handle charging. Some are just for data transfer or video output. If you’re not sure, look for a small battery icon near the port—that usually means it supports charging. Even if your laptop has a USB‑C port, it might not work for charging without the right charger.

USB Power Delivery (USB‑PD)

Most phone chargers use USB Power Delivery, which lets devices negotiate voltage and current. Laptops often need higher PD levels than phones. If your phone charger’s PD doesn’t match your laptop’s requirements, it may charge very slowly—or not at all.

USB‑C Cable Specifications

Not every USB‑C cable can handle high wattage. Basic or phone-only cables may support up to 3A at 5V (15W), whereas laptops may need 20V at 3–5A (60–100W). Using a cable that can’t handle the power can result in very slow charging or no charging at all.

Charger’s Wattage

Can you charge a laptop with a USB-C phone charger really comes down to your specific laptop and whether the phone charger can deliver enough power. A phone charger usually has a lower wattage than a laptop charger, which means it may charge your laptop very slowly or not at all. If the wattage is too low, your laptop might even lose power while in use.

How to Safely Charge a Laptop with a USB‑C Phone Charger?

The thing is, even though not all phone chargers are strong enough for laptops, USB-C charging can still be a safe and reliable option if done correctly. Here’s how to do it:

1. Check USB-C Port Compatibility:First, find the USB-C port on your laptop and see if there’s a small charging or battery symbol near the port. You can also check your laptop’s manual to confirm if it supports USB-C charging. And if it does, make sure the port supports USB Power Delivery (PD), which is required for charging laptops.
2. Verify the Charger’s Power:Check the output ratings printed on your phone charger. You’ll see something like “9V⎓2.22A,” which equals about 20W (9 × 2.22). Your charger needs to match or exceed your laptop’s power requirement; otherwise, it either won’t charge or will charge very slowly. If your current charger doesn’t provide enough power, a stronger option like the Anker Charger (130W, 6 Ports, GaN) is worth considering. With four USB-C ports and two USB-A ports, it can deliver up to 130W in total, giving you enough power to charge both laptops and phones with ease.

alt: Anker Charger (130W, 6 Ports, GaN)

3. Optimize Charging Performance:Before charging your laptop with a USB-C phone charger, close any apps or programs that use a lot of power, lower the screen brightness, and turn on battery saver mode. Make sure your laptop is placed in a well-ventilated area to avoid overheating, or choose a charger with built-in safety features, such as the Anker Nano Charger (45W) with USB-C Cable, designed with ActiveShield 2.0, which continuously monitors temperature to keep your laptop safe while charging.

alt: Anker Nano Charger (45W) with USB-C Cable

Common Pitfalls and Risks  

While charging your laptop with a USB-C phone charger can work in some cases, there are a few risks and mistakes you’ll want to avoid. Here are some of them:

1. Using a Low-Power Charger:Phone chargers usually don’t provide enough wattage. This can make your laptop charge painfully slow or not charge at all. In some cases, it may even damage the battery.
2. Assuming All USB-C Ports Support Charging:Not every laptop with a USB-C port allows charging. Some only use it for data or display, leaving you confused when your laptop doesn’t charge.
3. Overlooking Cable Quality: A poor or damaged USB-C cable can overheat, cause charging failures, or even short out your port. It also raises the chance of overheating or permanent battery damage.
4. Ignoring Charger Wear and Tear: Frayed cords and worn adapters are a fire hazard and can harm your laptop.
5. Leaving Chargers Plugged In: Keeping chargers connected when not in use increases the risk of power surges and faults damaging your laptop.

Conclusion

So, can a USB-C phone charger charge a laptop? The truth is, yes. But only if the numbers add up. Wattage, cable quality, USB-PD support, and USB-C port compatibility all play a role. A low-power phone charger might keep your battery alive for a while, but it won’t deliver the kind of steady performance most laptops need.

Anker has some of the powerful chargers that power both phones and laptops. Truly, once you’ve experienced a charger that actually keeps up with your laptop’s demands, you won’t want to go back.

FAQs

Is it safe to charge a laptop with a USB-C phone charger?

It’s generally safe, but not always practical. A USB-C phone charger usually has lower power, so your laptop may charge very slowly or not at all if it needs more wattage. For light laptops, it can work in a pinch, but gaming laptops or high-performance models need stronger chargers. It’s best to use the charger made for your laptop or one that charges both laptops and phones.

Why can't I charge my laptop with my phone charger?

Most phone chargers don’t provide enough power for a laptop. They usually have much lower wattage, which means your laptop may charge very slowly or not charge at all. In some cases, the issue could also be the cable. Some USB-C cables only transfer data and don’t support charging. Always check that both your charger and cable are designed to handle laptop charging.

Can I charge my laptop with a USB-C car charger?

It depends on the charger’s power output. While USB-C is universal, not all USB-C chargers are strong enough for laptops. Phone chargers usually don’t provide enough wattage, which can lead to slow or no charging. To charge your laptop properly, use a USB-C charger that matches your laptop’s power requirements and a cable that supports charging, not just data transfer.

How many watts does a laptop use?

On average, laptops use about 30 to 70 watts of power. However, the exact usage depends on the model and how it’s being used. Standard laptops typically fall within this range, while high-performance or gaming laptops can exceed 100 watts during heavy tasks. For comparison, desktop computers usually consume much more, around 200 to 500 watts.