WhatCable is a macOS menu bar app that identifies the capabilities of USB-C cables connected to your Mac.
USB-C cables vary dramatically in capability—from basic USB 2.0 charge-only connections to 240W, 40 Gbps Thunderbolt 4 cables—yet they all look identical. The Mac already exposes this information through IOKit, but the data is buried in system settings. WhatCable surfaces these technical details as a friendly menu bar popover, displaying in plain English what each connected cable can actually do and why your Mac might be charging slowly.
This tool suits anyone who owns multiple USB-C cables and wants to understand their capabilities without digging through technical specifications. It is particularly useful for troubleshooting slow charging or identifying which cables support high-speed data transfer or video output. The app works by querying existing macOS hardware information rather than inventing new detection methods, making it reliable on any Mac with USB-C ports.
The project is part of a family of related utilities including WhatBattery for battery health and WhatPort for comprehensive port information. Development shows consistent maintenance with regular updates addressing macOS compatibility and expanding cable detection accuracy. The codebase demonstrates attention to user experience through the menu bar interface design and clear presentation of technical information. The project maintains an active web presence with documentation and screenshots available on its dedicated website.
