I’ve bought many, many USB cables over the years. What frustrates me the most is how unassuming they are. Branded, braided, data-capable, high-speed, power-capable – these terms are meaningless to the average consumer when USB cables all look, more or less, the same. It’s a cable. It plugs in. It should all work the same, right?
If only it were that simple. I’ve bought many a dud in my time, even at prices that should have priced out the poor-quality knockoffs. Just because a cable has a fancy braided coating doesn’t mean that you can use it to power your laptop or smartphone, or that it’s safe to use for transferring data, or if it’s even safe to plug in without frying your USB port. That’s why I rely on a USB cable tester as part of my tech kit, and I think it’s one of those forgotten pieces of kit that every household should own, even if most probably don’t.
If it involves power, you really should test it
One unfortunate incident that occurred a few years ago that convinced me of this need involved a USB cable I purchased from a well-known retailing behemoth. I’ve owned a MacBook for several years and, if you’ve ever owned one, you’ll know the frustration of dealing with a yellowing USB charging cable. Every bend and every crease reduces the lifespan of the supplied USB power cable until, eventually, the plastic sheathing breaks, the wiring becomes exposed, and the cable ends up rotting in the trash.
So, to Amazon. I purchased a no-brand knock-off with a nylon-braided shielding that I hoped would work and would last. It didn’t. When it failed to charge my laptop after less than a week, it dawned on me that I was trusting my $2,000 MacBook to a cable that cost me less than $10. I didn’t know how it’d been made or if it was any good before I started using it, other than a cursory glance at the sketchy-looking packaging.
Give these USB testers a try
My inquisitive nature, despite being late to kick in, led me to consider how I could actually test a USB cable in the future before relying on it to power my devices or handle my data. I wouldn’t do it with a flash drive, so why would I do it to a cable? Hence: USB testers. You can test USB cables to determine their quality, available speeds, and generation. You can check if they’re grounded properly, provide the correct voltage and current, and check if they have any faults.
While some of these devices might look a little intimidating to beginners, they're easy enough to understand once you've given them a try. The most expensive will be designed to tell you upfront if, for example, a cable is ready and capable of handling the more advanced USB-C functionality – fast-charging, in particular, isn’t one you’ll want to trust to a cable that isn’t up to the challenge.
I've put together a list of a few USB testers that I would recommend. These vary in price and functionality, from basic tests to check the line and data capabilities of a cable, with more advanced models acting as USB multimeters that are capable of checking if features like fast-charging are working.
These USB testers should give you a good idea of how reliable your cables are. Beginners will probably find it easier to use the models with USB screens, like the Fnirsi USB tester or the MakerHawk USB Multimeter, but you can't really go wrong with any of them.
One thing to point out, however, is that to test a cable, you need a sacrificial lamb of a device to use it with. While testers like these should feature fault detection to prevent any damage, I use an old phone as my test subject, just in case. You should also remember that a cable is only as good as the device you use it with, although the USB multimeters we've listed here can help you check these, too.
And, if you find a cable you can't trust? Don't try to repair it, don't try to salvage it. The best place for it is in the trash — it'll save a whole lot of heartache.
