Skip to content
Jack Freiermuth
All projects
Demo2026

USB Cable ID

Plug in an unlabeled cable and the port map tells you what it actually is, instead of guessing from the connector.

TypeScriptReactNode.jsmacOS system_profiler

USB-C connectors say nothing about what is behind them. A cable in a drawer could be charge only, USB 2.0, 3.2 Gen 2, or Thunderbolt, and the only reliable way to tell is to plug it in and read what the host negotiates.

This walks the macOS device tree, renders it as a live port map, and tells you the negotiated speed and power delivery for whatever you just connected. It is small on purpose. It solves one annoying problem completely.

Details worth knowing

  • 01Reads the real device tree rather than inferring from connector shape.
  • 02Live port map that updates as cables are connected and removed.
  • 03One instance per machine, with the Windows port next on the list.