USB 3.1 Colour Codes: Convention, Not Specification
Teal became the shorthand for the faster tier, and then vendors started using it for other things. The colour on the plastic insert is a marketing habit, not a specification.
Quick Answer
There is no standard colour for USB 3.1. Blue is widely used for 5 Gbps SuperSpeed ports and teal or cyan is often used for 10 Gbps, but neither is enforced. Yellow, orange and red usually signal charging behaviour rather than speed. Confirm the rate by reading the negotiated speed in software or by checking a printed SS or SS10 marking.
Colour Associations
| Colour | Common association | Backed by standard |
|---|---|---|
| Black or white | USB 2.0 | No |
| Blue | USB 3.0, 5 Gbps | No |
| Teal or cyan | USB 3.1 Gen 2, 10 Gbps | No |
| Yellow | Charging while off | No |
| Red | High current or sleep and charge | No |
| Purple or green | Keyboard and mouse | No, legacy |
Why Vendors Use Colour
Differentiation
A coloured port is a visible feature. It helps sell motherboards with more fast ports than the competition.
User guidance
Colour gives users a quick hint about where to plug a fast drive, without documentation.
Cost of not doing it
Some manufacturers simply do not bother, particularly on laptops where uniformity looks better.
Verifying the Rate Instead
- Look for the SS trident, SS10 or a printed Gbps figure.
- Inspect the USB-A socket interior for the extra four contacts.
- Connect a known fast device and read the negotiated rate.
- Copy a large file and confirm sustained throughput.
- Record which ports are fast on your own machine and label them.
Real-World Applications
- Picking the right port for an external SSD without testing each one.
- Explaining why a teal port transfers at the same speed as a blue one.
- Mapping a docking station that has one fast port and several slow ones.
- Auditing hardware for a specification compliance check.
Related Guides
For cable generations, read USB 3.1 cable. For recognition methods, see how to recognize a USB 3.0 port. For actual speed tests, start with how to check a USB 3 port.
FAQ
Is a teal USB port always 10 Gbps?
No. It is a common convention, but some vendors use teal for 5 Gbps ports and others use it for charging features.
Why does my blue port transfer at 10 Gbps?
Because colour is cosmetic. The controller behind the port determines the rate.
Do USB-C ports use colour codes?
No. USB-C ports look identical regardless of capability. Documentation or a software check is the only reliable method.
What is the safest way to identify a fast port?
Plug in a known fast device and read the negotiated link rate.