What's the most durable USB C power cable

The answer is that all cables are disposable, get a cheap one with data features

I thought I’d write a brief blogpost answering about what’s the best USB C cable for charging phones and powering laptops.

tl;dr

You don’t want durability. You don’t want an “Abrams tank” version of a USB power cable. Beyond a few build quality issues, there’s no advantage. Pick the upper tier vendors (Apple’s own cables, Anker, etc.) and avoid the more obvious crap on Amazon.

What you care more about is features, like charging speed, data, and video. Just accept that your cables are going to age quickly and need to be replaced regularly. At least now you aren’t replacing the entire power supply when the cable ages.

Why charging cables break

Charging cables quickly break down during use.

One big reason is heat. Your laptop and charger get hot. There’s much more heat inside that what you feel on the outside touching them. Copper conducts heat, so a lot of that heat flows into the cable connector and down the cable wires.

This heat degrades the hard plastics from which the connector is built, and the soft plastics that cover the cable.

A lot of us have older power supplies and cables where the ends are falling apart. This is why.

We like to bend our cables more than physics allows. I’ve seen people tie their cables into tight knots and it freaks me out. Low quality cables have a single thicker strand that will break in such conditions, rendering the cable useless. Higher quality cables weave thinner strands together to achieve the same effective thickness. These are less likely to break when the cable is bent (the thinner it is, the more it bends). Moreover, when they do break, they simply cause cable resistance to increase a little.

Source: from Twitter

We abuse the connectors. This is one of the reasons Apple has gone back to their MagSafe connector even though their laptops can also be powered by USB C directly. It reduces the number of times we inadvertently break the connector, both on the cable end and the laptop end.

This is one of the reasons Apple stuck with their lightening connector for so long for their iPhones. The male connector on the cable was much weaker than the female connector in the iPhone, so that when you bent it, the cable would break before the phone. USB C cable connectors are too strong, which means accidents will damage laptops and phones more often.

Build quality (“like a tank”) can only go so far. Besides the really cheap cables that’ll fail quickly, even the most expensive cables can’t endure the punishment we give them.

Features matter, like charging speed

What matters more are the features of the cable.

All USB C cables are designed to carry 5 volts and 3 amps, for 15 watts of charging speed. What you want to look for is certified cables that actually match this specification. Non-certified cables use thinner copper wires, which cause a drop in voltage at 3 amps, such that they may no longer work.

This certification is for a minimum thickness of the copper wires carrying the current. The more current you pass through, the thicker the copper needs to be. The 3 amps required by the specification means that USB C cables are required to have thicker copper wires than the older USB A cables. By “required” I mean “by the certification”, which is why you want to look for certified cables.

The consequence of a bad cable is that voltage drops, so you might pump in 5.0 volts at one end, but get only 4.7 volts out of the other. Electronics are built to handle some drop, but around 4.7, a lot stop working, and batteries stop charging.

Good power supplies have circuits that can estimate the voltage drop, raising the voltage to something like 5.2 volts on one end so that something like 4.9 comes out the other. Thus, a marginal cable might fail with one power supply but work with another.

Instead of increasing current/amperage for more power, we can increase voltage. USB C comes with a “Power Delivery” specification that allows the increase of voltage.

When you connect to a USB C charger, the mobile device (laptop, phone, etc., the charger, and the cable all talk to each other to negotiate the amount of voltage and current available, and then choose the best profile that matches all three needs.

Older USB C Power Delivery standards have fixed voltages (5v, 9v, 12v, 15v, and 20v), and allow current/amperages to be negotiated up to 5amps. Thus, the maximum traditional power delivery has been 100 watts (20volts by 5amps). The latest power delivery standard allow many more voltages negotiated up to 48 volts, thus with a maximum of 240 watts. While a lot of cables have been upgraded to that spec (because that part is easy), chargers and laptops haven’t (because that part is hard).

When buying cables, you want ones that clearly advertise that they support “100 watts” or “240 watts”. Most of my older cables are 100w, because that was the maximum of the older standard. It’s really no more expensive for manufacturers to produce 240w cables (just more voltage, no more current), so that’s what I’d look for today.

It’s not really about wattage. My MacBook Air M2 can only draw 65watts, and my iPhone 15 can only draw 25watts, so all my cables are overkill. Instead, it’s the fact that meeting the max standard is pretty easy, so if companies aren’t, then they are probably doing hinky things underneath.

Their are exceptions to this advice. USB C power cable that comes with the latest iPhone 15 only supports 3amps at 20volts, or 60watts. This is not the full specification. But the feel of the cable is that it’s very easy to bend, using thin wires, which is probably the sort of cable you’d want from a mobile phone. Even this is overkill for the iPhone 15, which seems to only charge at 25 watts max. But it had a reason not to deliver max wattage — supporting 3amps instead of 5amps means a lighter, more bendy cable.

Data as well as power

The original question is about power/charging (I assume), but you need to factor in data as well.

The very low-end charging cables simply have no data at all. This tends to accompany bad build quality, too. It’s best to avoid them.

Average charging cables, though, still support some data, almost always 480mbps. If the cable is from a good vendor and they don’t mention data, then it’s still probably 480mbps, matching the old USB 2.0 standard.

If you want data, it’s best to search for that first. In other words, you want a data cable that supports charging rather than a charging cable that supports data. Such cables almost always support at least 3A at 20V or 60watts anyway, which is all I need to power my MacBook Air.

The minimum practical data cable you want is USB 3.1 Gen 2, supporting data at 10gbps. It’s also known as USB 3.2 Gen 2 (but not Gen 2x2, see below). You want to avoid the older 5gbps USB 3.0 (aka USB 3.1 Gen 1 aka. USB 3.2 Gen 1), not for any reason other than the fact they are no cheaper than the newer faster cables. Get new stuff when it’s no more expensive than the old stuff.

Video

Some USB 3 cables support video, but not all. If it’s not advertised as supporting 4k video, it probably won’t.

The actual feature is “DisplayPort Alt Mode” and it requires an additional pair of wires in the cable.

One of the many names for this is USB 3.2 Gen 2x2, where the “x2” means two sets of data wires. It’s is available for any USB 3 cable, including older 5gbps cables. USB 4 requires it, so at that point you don’t have to guess. Also, ThunderBolt 3 cables come with the extra wires as well.

If it supports the extra wires for DisplayPort, it’ll usually also support them for faster USB speed as well, so your 10gbps should now support 20gbps, though I can’t find anything that practically uses this. Most anything I plug in runs at 5gbps anyway, like USB C flash thumbdrives.

Road Warriors

We road warriors have a number of needs. We have a bunch of portable electronics.

In my travel kit, first and foremost I have a USB 4 (Thunderbolt 3), 240 watt cable. I don’t use it, I don’t want to wear it out or break it, but I have it for emergencies. It’ll support anything.

For my standard charging cable, I have just a cheap $10 cable recommended by Amazon that supports video, 10gbps, and 100watt charging. I expect to keep wearing it out and breaking it, though I haven’t yet. It’ll not only provide max power my laptop and phone can handle, but also support such things as video.

I have an emergency HDMI dongle for when I need to connect to a projector. There are many types of USB-to-HDMI converters out there that work on different principles. This one takes the DisplayPort AltMode signal and converts it to HDMI, so it requires a cable supporting video (like the ones I listed above).

For a charger, I use the Anker 735. It’s only 65 watts, but it’s all my MacBook Air can accept anyway. It’s lighter and smaller than Apple’s 65 watt power supply. I also carry the Apple 35 watt charger that came with the MacBook because it’s light and slender and easily packed, for emergencies.

Brands

Most of my USB cables and power supplies at home are from Anker, simply because that’s their brand.

I’m a capitalist and I understand how important a “brand” is to a company. Anker is the leader in this niche (USB charging). It seeks to defend its brand by not delivering crap. At the same time, it competes in a price-sensitive industry, so it’s not going to overcharge for its cable, even providing better ones. Also, as a leader, it’s got sufficient volumens of products in order to be able to deliver both low-price and high-quality.

I don’t know anything about the company other than they fit the model for capitalism, so I buy their products.

Apple is another company I’d trust. First all, there are numerous breakdowns and Apple chargers and cables on the Internet, and they are always insanely better than average crap you buy on Amazon. They are a bit more expensive, but are always very good.

Unlike Anker, they aren’t competing to be the best at USB power supplies, only that if you buy their product, you won’t be disappointed — which is what I actually want most of the time.

Conclusion

The original question (as I understand it) looks for the most durable USB C charging cable for travel. My answer is that you don’t want cables built like a tank, but cables that are disposable. This $10 Amazon cable seems reasonably well-built, is cheap, and has all the charging, data, and video features I need. I don’t mean to recommend this specific cable (it seems like one of the Shenzen fly-by-night companies), but it’s the sort of cable you should be looking for.

I do carry spares in case it breaks, is stolen, or (most likely) is accidentally left behind.

Around the house, I have other cables and chargers. I’ve moved almost everything to USB C — even devices that have only a barrel connector. Tossing all these DC power supplies has greatly improved my life.