If your MacBook, Lenovo, HP, Dell, or similar laptop runs out of juice, but you’ve forgotten the charger, try these ways to recharge its battery without the original power adapter.

It’s easy to forget to take a laptop charger with you. Notebook batteries hold enough charge for a few hours of run time, so you should keep your laptop charged to do the work you need.

Follow along for alternative ways to charge your laptop without its original charger. We’ll also discuss whether it’s safe to recharge a laptop without its official charger in the first place.

1. Charge Your Laptop Using a Power Bank

Much like how you’d charge your smartphone via a power bank when there’s no other way to recharge it, you can also use a power bank to charge your laptop.

Anker's PowerCore+ power bank

Anker’s PowerCore+ 26800mAh PD power bank is a great choice to charge up your Apple, Dell, Lenovo, or another laptop, as it outputs approximately 20 volts of power. Also, you’ll save a few bucks by consulting our roundup of the best power banks on sale.

As a rule of thumb, avoid power banks that put out only 5V, as most laptops need 8V-12V power. Choose ones that support laptop charging and USB-C (early generations of laptops with USB-C don’t support charging).

2. Charge Your Laptop Using a Car Battery

Car hood open, with the battery being charged

If you can’t manage a power bank, your car’s battery can charge your notebook without a charger, but you’ll need a power inverter to convert the DC power from your car to AC.

An accessory like the BESTEK 300W Power Inverter outputs up to 300 watts—more than enough to power a laptop! Although you’ll need to leave the power inverter somewhere on the vehicle floor, you can still take your laptop inside and out—which is excellent for beginners.

3. Purchase a USB-C Power Delivery Charger

If you don’t have a power bank or can’t charge your laptop using a car battery, another good solution is a USB-C power adapter with multiple ports, sometimes referred to as a USB PD charger.

The front of Satechi's 108-watt USB-C desktop charger with two USB-A and two USB-C ports

Of course, these things must be plugged into power vs. being a power source by itself, like a power bank. Satechi’s 108W USB C PD Desktop Charger (or your favorite brand) would recharge your laptop the same as a power bank.

Choose a charger with the right mix of USB ports to support all your devices. USB-C has a smaller oval-shaped connector that’s reversible and designed to conduct much more power at higher speeds than the older USB-A port. This makes it an excellent alternative for charging your computer when you don’t have a charger. Furthermore, power adapters compatible with the USB Power Delivery protocol (USB PD) feature protections against overcharging, overheating, etc. As such, they’re among the safest methods to charge via USB-C.

There are plenty of different chargers out there. To help you choose the right one, see our roundup of the safest and best USB-C chargers you can buy today.

4. Invest in a Universal Power Adapter

While it’s great to know that there’s another option to charge your laptop battery without needing the official charger, you’ll probably end up with a dead or failed battery if you set the voltage too high when using a universal power adapter.

Universal power adapter with interchangeable tips

It usually comes with interchangeable tips, with many different brands supported. Some battery packs even work with your car’s 12-volt cigarette lighter, making them truly portable.

5. Use a Super Battery for Your Laptop

Super batteries are like second or spare batteries for your laptop. They have different charging cables, and they replace your original laptop battery.

Ensure it fits your laptop and is the right size when you get one. Super batteries are brand-specific and may not work with your laptop if they weren’t explicitly designed for it. This method isn’t efficient, so it’s only for emergencies.

6. Keep a Spare Battery for Emergencies

A laptop with a dead battery can kill your productivity. Plan ahead by investing in a spare battery, but pick one for your specific laptop brand and model.

Dell Latitude Battery Replacement

Unlike super batteries, these are regular batteries that don’t require different charging cables. A spare battery is a life-saver for those times when your laptop’s battery has run out, and none of the alternative charging methods are currently available.

7. Use Your Computer’s USB Port for Charging

You can connect your laptop via a cable to another computer’s USB-C port to recharge its battery. USB-A ports won’t work, so be sure to plug the laptop into the computer’s USB-C port.

However, you should note that if the charger or charging port cannot provide the required voltage, the laptop will charge slower than usual. This is normal and nothing to worry about.

8. Buy an External Battery Charger

An external battery charger enables you to recharge your laptop’s battery when it won’t charge due to a faulty motherboard or DC socket.

External battery charger for Lenovo's Thinkpad laptop

Provided your computer has a user-removable battery, take it out and mount it on your external charger. Connect the charger to power and wait until the flashlights indicate the process is finished, then reinstall the battery in your laptop. That’s it—you’re good to go!

Pick an external battery charger specifically made for your machine. External battery chargers aren’t universally compatible across laptop brands.

9. Use a Phone or Tablet to Charge Your Laptop

iPad with keyboard case next to MacBook

Many smartphone brands like Samsung and some tablets like iPads support reverse charging, meaning they act like USB power banks.

On Android, you may need to enable this capability in settings. Otherwise, connect your laptop to the tablet’s USB-C port to give it a quick battery boost when you need it most.

However, you should limit reverse charging to emergencies to avoid overheating the battery in your phone or tablet, which can shorten its lifespan.

Is It Safe to Charge Your Laptop Without Its Official Charger?

If the voltage and power don’t match the specifications of your laptop’s original charger, it may be unsafe to use different charging methods. The official charger or its approved replacement is the best way to safely power your laptop in all scenarios. Another common question we previously covered is, “Should you leave your laptop plugged in all the time?

Unfortunately, there is no easy answer:

Does leaving your laptop plugged in ruin the battery? Yes, it does. But then so does charging it every day.Curiously, the industry as a whole doesn't seem to have settled on a single answer for the question about whether to use your laptop on AC or battery power.

Most manufacturers advise against leaving your laptop plugged in at all times.

Don’t Leave Your Laptop Charger at Home!

Some of the above methods can be unsafe for your laptop battery’s longevity, so avoid using them regularly unless urgent. Always use the official charger with your laptop; resort to these methods only when necessary.

To avoid interruptions in your work, it’s smart to invest in an external power adapter or a USB-C charger and always carry a spare battery. Forgetting your charger at home is annoying! Next time when packing your bags, throw your chargers in before thinking about everything else.