About
WhatCable is a small macOS menu bar app that tells you, in plain English, what each USB-C cable plugged into your Mac can actually do and why your Mac might be charging slowly. It uses information macOS already exposes through IOKit and presents it as a friendly menu bar popover. For each port, it shows an at-a-glance headline, such as Thunderbolt / USB4, USB device, Display connected, Charging only, or Nothing connected, along with a charging diagnostic that identifies bottlenecks like a cable rated below the charger.
The app also reports cable details, including the cable's data speed, current rating, and USB-IF certification status, and flags unusual e-marker values with hedged wording. It lists the charger's voltage profiles and highlights the one currently in use. Connected devices are shown within the hubs or docks they are plugged into, with hubs hidden by default and available on request. For Thunderbolt and USB4 links, it displays per-lane speed, generation, and switch topology. WhatCable is part of a family that also includes WhatBattery and WhatPort, and it offers desktop widgets that show live cable status.
What's new
All release notesHomebrew cask whatcable 1.5.0 (sha256 92f42a5485577c560f944c7020cdcf0dd3fcc919e2de80ab699dce3d608b888b).