darrylmorley/whatcable

Health v2 · maintenance only

Flags: young no_license

Adoption not part of the score

8553 stars · 260 forks observed · 2026-08-28

What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-29, confidence not recorded

WhatCable is an open-source macOS menu bar app that reads IOKit data to explain, in plain English, what each connected USB-C cable, charger, dock, or device can actually do. It diagnoses charging bottlenecks, data-speed limits, cable e-marker identities, and mid-session port faults, with an optional paid Pro tier and a bundled CLI.

Use cases

• figure out why my Mac is charging slowly
• identify what a USB-C cable can actually do
• check if a cable supports Thunderbolt or USB4 speeds
• find out which part of my USB-C setup is limiting data speed
• read a cable's e-marker power and speed rating
• diagnose an external SSD that keeps disconnecting
• check whether my 4K display is running at full refresh rate
• troubleshoot a dock that negotiates differently on different Macs

When to choose

• you need plain-English USB-C and Thunderbolt diagnostics on an Apple Silicon Mac
• you want to identify unlabeled cables and their real capabilities
• you're debugging slow charging or degraded data links on macOS
• you want a free, signed, no-setup menu bar utility with an optional CLI

When to avoid

• you need USB-C diagnostics on Windows or Linux
• you're on an Intel Mac or macOS 13 or earlier
• you need raw low-level IOKit dumps rather than interpreted verdicts
• you need cross-platform or headless-only tooling without a GUI

Facets

application · maturity active

developer-tools gui hardware developer-tools usb-c thunderbolt usb-power-delivery menubar-app swiftui hardware-diagnostics apple-silicon iokit cable-diagnostics macos desktop

Member repositories

For agents

markdown · JSON · MCP: product_card(name="darrylmorley/whatcable")