Key Takeaways
- Using old or cheap USB-C cables can not only result in slower charging speeds but also pose risks such as damaging your devices or causing a fire.
- Not all USB-C cables are created equal, with some being capable of faster data transfer speeds and higher power delivery than others. It's important to invest in high-quality cables to avoid potential damage.
- Signs that your USB-C cable may be unsafe to use include fraying, loose wires, or decreased charging speeds. Testing the power delivery output and data transfer speeds of your cables can help determine their quality and safety.
Before you pick up that cable you haven’t used in years to charge your phone or transfer data to your computer, you might want to test it to ensure it’s safe to use. Here's how to do so.
Many people are aware that using an old or cheap cable may result in slower charging speeds, but it’s possible for these lackluster cables to damage your devices as well. Some signs of danger are more obvious than others, like a frayed cord, but other potential risks can be invisible to the naked eye.
Luckily, there are ways you can examine or test your existing cables to determine whether they should be kept or thrown out. There are also a few physical cues to look out for when a cable is in your regular rotation. With a few simple actions, your home could be free of any cable that could cause damage to your smartphone, laptop, or other devices.
How Can Bad USB-C Cables Damage Your Device?
Our focus is on USB-C cables because, unlike their earlier predecessors, they are capable of delivering significantly more power to devices which means when things go wrong the stakes are much higher. The chances of a USB-C cable doing damage to your device are slim, but it can happen. In the worst case scenario a bad cable can fry a port, damage a battery, or even cause a fire. With a little bit of awareness and ensuring you're using high-quality USB-C cables, you can make sure you don't end up a cautionary tale.
Not All USB-C Cables Are Made Equal
Many USB-C cables are able to charge and transfer data between your phone and other devices. A top-tier USB-C cable is capable of transferring data at speeds up to 10Gbps, while lower-quality cables can only transfer data at 5Gbps or even 480 Mbps.
Then, some USB-C cables are charging-only, meaning they’re not capable of carrying out data transfer between your smartphone and another device. When you find a cheap cable at a gas station or in the grocery store checkout line, it’s probably a charging-only cable. With these charging-only USB-C cables, the main difference is how much charging power it’s capable of.
Some cables support fast-charging speeds up to 100W, while others may only be capable of as little as 2.5W of power delivery. Unless you have the cable’s original packaging (and sometimes, even if you do), it’s difficult to tell how much power delivery the cable supports without a physical tool to test it.
To the naked eye, all USB-C cables look the same. There are some cables that are USB-C to USB-C, while others are USB-C to USB-A—that’s the only visual difference you can spot. But not all USB-C cables are Thunderbolt cables capable of fast power delivery and data transfer, and the only way to tell what your cable is capable of is by investing in a USB testing device.
What Kind of Damage Can Bad USB Cables Cause?
There’s potential danger in connecting your phone to a charger and cable with a higher power delivery output if your phone can’t regulate how much power it’s letting in. Many modern smartphones will only take as much power as they need, but if your phone can’t, you risk your phone, or even the cable, overheating. This is increasingly less of a problem with phones as they have more sophisticated charging circuits, but cheap gadgets like white-label speakers, flashlights, toys, and other inexpensive devices may not.
In worst case scenarios, a device that’s overheating can explode or burst into flames. Cheaper USB-C cables are made with low-quality components that may not be able to hold heat as well or as stably, so there’s an extra overheating risk with these cables.
Using a USB-C cable that delivers too much power to a device that requires less can also damage that device’s battery. Again, modern smartphones have built-in protections to prevent overcharging or charging too quickly, but cheaper, older smartphones or other devices that charge via USB-C may not.
It’s also possible for a bad cable to damage your PC if it breaks or shorts out when it’s connected. Benson Leung, a Google engineer now known for reviewing USB-C cables for safety, found this out when both of his Pixel Chromebook’s USB-C ports stopped working and eventually put his laptop into recovery mode. A bad cable can cause irreversible damage to your PC’s ports or other components.
To prevent damage to your computer’s internal components and overheating risks, you’ll want to find a high-quality, reliable USB-C cable. In fact, when you find an amazing cable, you might consider investing in a few of them—one for every room, for your car, for your travel backpack.
How Can You Tell If Your USB-C Cable Is Bad?
If a USB-C cable is bad, you shouldn't be using it, naturally. But how do you know when it's not safe to use anymore?
Signs Your Old Cables Should Be Tossed
Some indications of a dangerous cable are obvious, like a fraying cable with exposed wires. When a cheaper USB-C cable is made with a flimsy material, it can fray easier and expose the wires faster than a sturdy cord material would. Or, the wires could be loose inside even if the cord looks solid from the outside.
It's worth noting that while you should obviously toss frayed cables, you shouldn’t just toss a cable because the material doesn’t feel great. That cable may be made with a less-than-stellar material, but otherwise function perfectly.
You’ll need to look harder to spot more niche signs that your cables should be tossed. Pay attention to how well your phone charges with certain cables. Does it charge four times slower than your best cable? Does it say it’s charging, but not really boost your battery percentage at all after hours of being plugged in? Does it stop charging your phone at a certain percentage?
Paying attention to how well your phone charges with your USB-C cables can also help you spot when a cable is starting to fail, and not just bad right out of the box. If your phone used to take an hour to fully charge with a cable, and now it takes an hour and a half, it’s time to inspect your cable, charging block, and smartphone to figure out the issue.
How to Test Your Existing USB-C Cables
Testing your cable’s data transfer speeds is pretty difficult, but you can test the charging speed of your USB-C cables with the easy-to-use AVHzY C3 USB-C tester. This compact tester needs power supplied to it through one USB-C port, and then you can plug in the USB-C cable you’re trying to test to see detailed information.
AVHzY USB Power Meter
TheAVHzY USB Power Meter makes it easy to test any USB-C cable to ensure cable integrity and safety. While not everyone needs a dedicated cable tester, if you want to be absolute sure your cables are safe or you have lots of cables to test it's a worthy investment.
$66 at Amazon
You can see whether the cable contains the E-Mark protocol controller required by the USB Implementers Forum (USB-IF) organization for cables that meet certain power delivery and data transfer speed minimums. Because it’s not highly regulated, some manufacturers will say their cable contains an E-Marker (indicating it meets those minimum required speeds) when it really doesn’t, so having a tester lets you know definitively.
This USB-C tester can also tell you how many volts and amps are outputted when the cable is plugged in, keying you into the maximum wattage of your cable. Knowing this information can help you not pair a cable that’s too powerful with a device that requires lower wattage.
Or, if you’d like to invest in an item that can charge your devices as well as display vital information about its power delivery capabilities, check out the Baseus Blade 20,000mAh portable charger. On the display, you can see how many volts and amps are going through the cable to your device, and use this information to determine wattage output.
Baseus 100W Laptop Power Bank
The Baseus Laptop Power bank not only sports 2 USB-C Power Delivery ports to help you fast charge your laptop and other devices, but it has an LED status display that offers an indepth look at the charging stats so you can assess how effectively your cables are functioning.
To find out your cable’s rated data transfer speeds, you can see if there’s a number or a SuperSpeed (SS) indicator by the USB symbol. Testing the actual data transfer speed of your cable requires time, lab equipment, or both.
That said, a mismatched power delivery rate is more dangerous than a mismatched data transfer rate, so testing your cable’s power delivery output is more important.
How to Find a Good, Safe Charging Cable
If you've come to the conclusion that all your existing USB-C cables are no good, it's time to buy some more.
What to Look for in a USB-C Cable
Although modern smartphones often don’t come with a charging block, they still come with a charging cable. Most mainstream smartphone manufacturers make high-quality, reliable cables, but that’s not always the case. For example, iPhone cables—which aren’t USB-C cables yet—are more prone to fraying than cables from Samsung or Google.
If you have the budget and the time to do so, you can always test your existing USB-C cables, see which ones perform the best, and invest in more of your best cables. Or, if you want to invest in new USB-C cables, check out reliable power brands with USB-IF-certified cables, like Anker, Cable Matters, or Belkin. Splurging on a quality cable is worth it in exchange for ruining your pricey smartphone.
When you're looking for a new USB-C, you should definitely consider the cord material. Some of the best USB-C cables are made with a nylon weave cord that's sturdy and less prone to fraying over time with consistent use.
User reviews are incredibly useful when searching for a reliable USB-C cable. If someone has a bad experience with a USB-C cable, they’re going to talk about it on Amazon, Best Buy, or wherever they bought the cable from. You can learn from someone else’s bad experience, and steer clear of cables that may cause your device to overheat or cause damage to your computer when transferring data.
Recommended High-Watt USB-C Cables
If you want to skip doing the research yourself, be sure to check out our roundup of the best USB-C cables. It's tough to go wrong with high quality cables like the New Nylon cables from Anker. If you don't like the look of those cables from Anker, any other USB-C cable from this company will be a high-quality, reliable purchase.
Anker New Nylon USB-C to USB-C Cable
Anker's New Nylon line of USB-C cables offers high durability and high-wattage Power Delivery charging.
Alternatively, you can save a little bit of money and still get a USB-IF-certified cable with these AmazonBasics Double-Braided Nylon cable. Or, splurge on Belkin's Thunderbolt 4 USB-C cable to get fast data transfer speeds.
