Can you use a Dell charger on an HP laptop? Or vice versa? I don’t recommend it, but sometimes you can. In a pinch, that’s better than not being able to use your laptop at all. Here’s how to tell.
Laptop chargers aren’t like phone chargers
Phone chargers are almost always interchangeable among brands. Laptop chargers aren’t nearly as standardized. So even though your buddy’s LG charger works fine on your Samsung phone, you can’t assume that means you can use a Dell charger on an HP laptop too.
Ideally, the laptop will protect itself from a charger that outputs incompatible voltage. But you can’t assume it will. Making matters worse, HP and Dell don’t want you interchanging their chargers with each other’s laptops. Sometimes, if the chargers are close enough, they’ll work. Sometimes they’ll work partially but give you nasty messages saying you need to use like-branded equipment. Sometimes they won’t work at all.
Yes, normally you can interchange AC adapters, but HP and Dell power bricks aren’t just simple AC adapters. They have a little bit of extra circuitry in them so the laptop can tell if you’re mixing brands. There’s an extra pin in the center of the plug that this circuitry uses.
What to do if your laptop isn’t turning on
If your laptop isn’t turning on and that’s why you’re interested in trying a wrong-brand charger, try a different fix first. Remove the battery, unplug the charger, then hold down the power button for about 15 seconds. Then replace the battery, plug the correct charger back in, and try to power the laptop back up. I’ll bet you it works. And it takes about a minute to try. I go into more detail on that fix here.
If you have one of the super-thin laptops that doesn’t have a removable battery, try holding the power button for 30 or even 60 seconds to trigger a reset.
While laptop chargers can go bad and theoretically will eventually, I can’t say I ever saw an original HP or Dell charger go bad. They’re really rugged and tend to outlive the laptops they came with. If your laptop is refusing to turn on or charge, it’s more likely to be a momentary glitch than a problem with your charger, assuming it’s an original.
What to do when you really need to substitute a charger
If you need to substitute chargers because you misplaced or forgot yours, then my trick above won’t help you of course. You have to identify whether the wrong-brand charger you have even stands a chance. Here’s how to evaluate it.
Does it even fit?
Just because it fits doesn’t mean it’s OK to use, but sometimes the connector doesn’t even fit. Try the fit without the charger plugged into the wall to see if it’s even a candidate to use.
Polarity is the most important question. If the polarity is reversed, it can damage the laptop. This can be tricky because HP is bad about omitting the polarity symbol or printing it illegibly small.
The symbol looks like the tip of your plug. The symbol will indicate whether the center is positive or negative, and whether the edge is positive or negative. Normally the symbol is printed both on the power supply and on the back of the laptop, by the power plug.
If your laptop or AC adapter doesn’t have the symbol, you have some homework to do. Search Ebay for a third-party adapter for the laptop in question, or a third-party substitute for the charger. Zoom in on the picture to check the polarity. Third-party replacement bricks almost always have the polarity printed on their labels. If you find one that doesn’t, keep scrolling until you find one that does.
I did spot-check every Dell and HP charger I own. I happen to own three different models of each, and in all cases, they were center positive. That doesn’t guarantee everything Dell and HP ever made, and will make in the future, is center positive.
Voltage mismatch is another problem. If they’re close it’s OK; an 18.5-volt adapter and a 19.5-volt adapter are close enough. If the deviation is more than about 10 percent, that can be problematic. Overvoltage causes excessive heat, and undervoltage generally causes instability.
Wattage can be tricky. Too low is a bigger problem than too high, but crazy-high wattage can potentially be a problem too. It seems like 45 and 65 watts are the most common. Try to match wattage as closely as you can. Some laptops require 100-watt beasts of a power brick, and if yours happens to be one of those, a wrong-brand 45W adapter isn’t going to do much for you.
Plugging in a 100-watt beast into a system that normally uses a svelte 45-watt mini-brick shouldn’t be a problem under normal circumstances, but if anything goes wrong, it can deliver excess voltage that a properly spec’-ed power brick wouldn’t.
Under-wattage is a bigger problem. If you plug a 45-watt brick into a system that wants 65 or 100 watts, the 45-watt brick will try to deliver what the system asks for. It will eventually overheat and die trying.
Substituting a 65-watt brick for a 45-watt unit won’t be a problem.
Found a match?
If you found a reasonable match, all that’s left to do is plug it in and see what happens. With some luck, it’ll work. I really don’t recommend using wrong-brand adapters long term, but if it gets you through your emergency and you don’t make a habit of it, you’ll probably be OK.
You may find that the adapter powers the laptop but refuses the charge the battery. If that’s the case, there’s nothing you can do about that. It’s a safety feature. The two devices may even refuse to work together, and just flash lights at you. If that happens, there’s nothing you can do about that either. At least you tried.
Can you use a Dell charger on an HP laptop?
So, can you use a Dell charger on an HP laptop? Since every HP and Dell adapter I could find to check use very similar outputs, it’s possible the two companies made a conscious design decision, knowing people are inevitably going to mismatch adapters and laptops. They don’t want you interchanging them. But it seems like both companies went to some lengths to avoid damaging each other’s stuff.
I can’t guarantee results. And I know sometimes it doesn’t work. But at least it doesn’t look like a sure-fire way to break something either.