Free Mac App WhatCable Reveals USB‑C Cable Performance

A new utility for Apple‑silicon Macs is giving users a free, built‑in way to evaluate the performance of their USB‑C cables after the discontinuation of a popular $8 hardware tester. The app, called WhatCable, taps into diagnostic information that macOS already gathers about connected USB devices—data that Apple does not normally expose to end users—and presents it in a simple menu‑bar widget. By clicking the widget, users can instantly see whether a cable is capable of high‑speed data transfer, power delivery, or if it is limited or faulty.

WhatCable’s functionality mirrors the earlier handheld tester that identified “fast, slow, powerful, or weak” cables, but it does so without additional hardware and at no cost. The software reads the cable’s electronic identifiers and reports its specifications, allowing consumers to verify the quality of third‑party or older cables directly from their computers. The tool expands the utility of Apple’s own diagnostics, offering a convenient solution for anyone needing to confirm cable performance in a growing ecosystem of USB‑C accessories.