WhatCable: Know What Your USB-C Cable Can Really Do
WhatCable is a macOS menu bar app that provides clear diagnostics on USB-C cables, revealing their actual data speeds, charging limits, and connected device details to eliminate guesswork. It decodes USB Power Delivery and e-marker data on Apple Silicon Macs, helping users identify bottlenecks, cable capabilities, and potential issues, with a free version for basic info and an optional Pro upgrade offering advanced live diagnostics and detailed metrics.






