I admit that much of my motivation for writing this explainer is selfish. As someone who has used and reviewed technology for decades, USB color coding is one of those anecdotal items that has entered and exited my consciousness several times over the years, but never found enough purchase to really stick. It’s not something that comes down to knowing what type of USB port you have. We hope that a dedicated article explaining why most USB-A ports are color-coded and why most USB-C ports are not will help house it in the old gray matter.
The TL;DR is that USB-A ports are largely color-coded to indicate which USB generation they support. You might then assume, especially given its simple, reversible form factor, that USB-C doesn’t require color coding due to certain universal and standardized capabilities. Unfortunately, the exact opposite happens: USB-C lacks color coding because there are too many variables to be easily indicated with a single color.
What the Colors Mean (and Why USB-C Lacks Them)
Despite a true painter’s color palette, things are easier on the USB-A side. Here is what the different colors indicate:
- White is the OG, which in this case means the original generation. White indicates devices in USB 1.X version.
- Black covers generation 2.0 of USB-A.
- Yellow is the first split color, which means it can support standard 2.0 or the new standard 3.0. It also indicates an “always on” port, which can provide power even when the device it belongs to is powered off.
- Orange means a purely 3.0 port or device and is also “always on”.
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Blue is also a USB 3.0 connection, but without the always-on functionality.
- Teal is for USB 3.1.
- Red indicates a USB 3.1 Generation 2 and USB 3.2 port or device, the latest USB-A versions.
USB-C poses a problem for this type of simple categorization system, because a single USB connection can support USB 2.0, 3.x, or USB4 data speeds, DisplayPort or HDMI video output, Thunderbolt 3, 4, or 5, and power delivery from a few watts up to 240W. You would need a dizzying rainbow of colors to indicate what amalgamation of speed, power, video capacity, and protocol supports a single USB port or device.
Why it matters
On the USB-A side, the colors mainly designate the generation. This is primarily important because each generation supports different transfer speeds. USB 1.X (white) reaches 12 Mbps, USB 2.0 (black or yellow) reaches 480 Mbps, USB 3.0 (yellow, orange or blue) up to 5 Gbps, USB 3.1 (teal) also reaches 5 Gbps, USB 3.1 Gen 2 (red) can reach 10 Gbps and USB 3.2 (red) can reach a maximum of 12 Mbit/s. 20 Gbps. USB-C, on the other hand, is capable of much faster speeds.
The Thunderbolt protocol, which works over USB-C, for example, can achieve transfer rates of up to 40 Gbps, while the new USB 4.0 reaches even higher, up to 120 Gbps. The issue with lack of color coding on USB-C can cause downstream confusion. You may plug a brand new external SSD into your laptop and wonder why the speeds are fixed at USB 2.0, or wonder why you can’t get a monitor that requires DisplayPort Alt mode to work on certain ports. Fortunately, Thunderbolt and USB4 seek to remedy some of these headaches by unifying their capabilities.