The USB-C cable you should actually buy

A USB-C cable can carry 60 watts or 240. It can move data at 480 megabits per second or 80 gigabits. It can drive a 4K monitor at 120Hz or refuse to drive one at all. From two feet away, every one of those cables looks the same.

This is the last unsolved part of the USB-C transition. The connector is universal; the capability behind it is not, and the packaging is under no obligation to tell you.

Key takeaways

• —A cable has three independent ceilings — power, data and video — and a high rating in one implies nothing about the others.
• —Most cables in a drawer are 60W/USB 2.0, including the ones that came with expensive hardware.
• —Buy for the highest ceiling you own, not the device in front of you, and buy short.

Three ceilings, not one

The mistake almost everyone makes is treating "USB-C cable" as a single specification. It is three, and they are set independently.

Power. The floor is 60W (20V at 3A). Anything above that requires a chip in the connector — an e-marker — that tells the charger the cable can handle more current. Without it the charger refuses to exceed 60W, correctly, because it has no way to know the cable is safe. 100W and 140W cables are common; 240W exists and is worth having only if you own something that draws it.

Data. USB 2.0 at 480 Mbps is the default, and it is what most bundled cables ship with. USB 3.2 at 10 or 20 Gbps requires additional conductors and better shielding. Thunderbolt 4 is 40 Gbps; Thunderbolt 5 is 80. A cable rated 240W for power can still be USB 2.0 for data, and frequently is — the two run on different pins.

Video. DisplayPort Alternate Mode is what lets a USB-C port drive a monitor. Whether a given cable supports it, and at what bandwidth, is a third independent question. This is where people get caught: a charging cable that works perfectly for a laptop will connect a monitor at a reduced resolution or refuse entirely, and the failure looks like a broken monitor rather than a wrong cable.

What the logos actually mean

The USB-IF's certification program is the only reliable signal, and its 2023 revision made it genuinely useful: certified cables now print the wattage and the data rate directly on the connector housing. A cable that says "240W" and "40Gbps" on the plug has been tested to do both.

The catch is that certification is voluntary and the marketplace is full of uncertified cables that describe themselves in whatever terms they like. "Fast charging" is not a specification. Neither is "supports 4K", which is technically true of a cable that manages 4K at 30Hz — a refresh rate that makes a mouse cursor visibly stutter.

The practical rule: if the numbers are not printed on the connector, assume the cable is 60W and USB 2.0. Most are.

What I would buy

One good cable beats four mediocre ones. The honest recommendation is to buy for the highest ceiling in your house and use that cable for everything, rather than maintaining a collection you cannot tell apart.

For most people that means a 240W, 40Gbps cable. The Anker 240W is the reference point — certified, marked on the connector, and priced like a cable rather than an accessory.

If you own a Thunderbolt 5 machine and an external drive fast enough to saturate it, the Cable Matters Thunderbolt 5 is the one that will not be the bottleneck. For anyone else it is a waste: Thunderbolt 5 costs roughly three times a good USB-C cable and does nothing measurable unless both ends support it.

Buy short. Signal integrity falls off with length, and above about a meter a passive cable starts dropping its data ceiling even if the power rating holds. A two-meter 40Gbps passive cable does not exist; the ones advertising it are active cables with electronics in the plug, which cost several times as much and can be directional.

The three-cable setup

After years of accumulating cables, this is what actually works:

1. One 240W/40Gbps cable at the desk, 0.8m, for the laptop and anything docked.
2. One 100W/USB 2.0 cable in the bag, 1.5m or 2m. Charging while travelling does not need data throughput, and the longer cable is genuinely more useful.
3. One short 60W cable for phones and earbuds, kept where the phone lives.

Anything beyond that is a cable you will not be able to identify in six months.

What to check before you buy

• Wattage and data rate printed on the connector, not just in the listing.
• USB-IF certification, with a listing you can actually look up.
• Length — shorter is better, and 0.8–1m covers most desk use.
• Whether it is active or passive at 2m or longer, because active cables can only be run in one direction.
• DisplayPort Alt Mode support, explicitly stated, if a monitor is involved.

None of this is hidden. All of it sits below the fold on a product page, underneath a headline number that describes only one of the three things the cable does.