We often buy expensive cables without knowing if they can actually drive our monitors at full resolution. WhatCable solves this uncertainty by revealing the exact capabilities of your USB-C connections on macOS. This utility helps MacBook owners verify that their hardware matches their display expectations before they encounter black screens or reduced refresh rates.
Utility helps verify cable bandwidth for external displays
The app runs as a background service and displays maximum data rates and USB-C Power Delivery profiles via a menu bar icon. It supports MacBook Pro, MacBook Air, MacBook Neo, Mac mini, and iMac models. Users can quickly check if a connected cable supports the bandwidth required for their specific external display setup.
- Supported Devices: MacBook Pro, MacBook Air, MacBook Neo, Mac mini, iMac
- Pricing: Free (Basic), £9.99 / $13 (Pro)
- Functionality: Displays maximum data rate and supported USB-C Power Delivery profiles for each cable
WhatCable identifies the maximum data rate and supported charging profiles for each connected cable. The tool works by reading the electronic marker (E-Marker) chip present in most modern cables. This data allows users to confirm if a cable supports high-speed data transfer or if it is limited to slower speeds.
The app cannot provide data rate information for inexpensive cables that lack an E-Marker chip. In those cases, it displays only the power transmission capabilities of the cable. Additionally, the app incorrectly identifies a Thunderbolt 3 cable connected to a USB device as a USB 2.0 cable with a 480 Mbit/s limit.
WhatCable is available for free with basic functionality. The Pro version offers additional insights for a one-time fee of £9.99, which costs around $13. This pricing structure allows users to test the tool without upfront cost before deciding if the advanced features are necessary for their workflow.
Source: Free app, NotebookCheck
