WhatPort shows the protocol, speed, lane status, and power draw for every USB-C and Thunderbolt port on your Mac. Real-time data, no guessing.
The app is free and open source. Pro adds the Flight Recorder · View source
The ports on your Mac are identical holes. One might be Thunderbolt 5, the next plain USB. macOS won't tell you which is which, why a charger crawls, or whether your display is running at full resolution. WhatPort does.
TB5, TB4, and USB-C ports look identical. Plug your fast SSD into the wrong one and it crawls, with nothing on screen to tell you why.
A port might be negotiating a fraction of the power you think. WhatPort shows the live watts, voltage, and current, so you can see the limit.
DisplayPort alt-mode can quietly run at reduced lanes or link rate. WhatPort shows the lanes in use and the negotiated speed per lane.
WhatPort identifies what each port is carrying and colour-codes it so you can tell at a glance whether you're on Thunderbolt, DisplayPort, USB, or just charging.
TB3, TB4, and TB5. Lane width, speed per lane, and link generation.
DP alt-mode with lane count, link rate (HBR2, HBR3), and display resolution.
USB 2.0 through USB 3.2 Gen 2x2. Device name, speed, and version.
MagSafe and USB-C power delivery. Live watts, voltage, and current draw.
WhatPort reads real-time data from IOKit and turns it into something you can actually understand. No terminal needed.
See which lanes are carrying data and at what speed. Each lane shows its transport protocol and power state in real time.
Real-time power in and out for every port, with wattage, voltage, and current. A rolling 60-second graph shows draw over time.
Connected devices show product name, vendor, serial number, USB version, and current draw. Thunderbolt docks are named by their own controller.
Native resolution plus link rate (HBR2/HBR3), lanes in use, native versus Thunderbolt-tunnelled, display count, and any hub or HDMI converter in the chain.
Lifetime connection counts and error tracking per port. Spot overcurrent events, link errors, and enumeration failures.
Cable type (active/passive) and USB PD revision detected from the cable's e-marker data.
What the port has actually set up (USB 2, USB 3, DisplayPort, and so on), and a flag when macOS has blocked one. The usual reason a dock's USB or display won't work.
When a charger is plugged in but not charging, WhatPort says why: charging, fully charged, held to protect battery health, or simply not charging. Never a guess.
Names the connected adapter and lists its full advertised power menu, so you can see a 96W brick is a 96W brick even when little is being drawn.
Flags a wet port before corrosion sets in, with advice to disconnect and dry it out (M3 and later).
Every port expands to show lanes, Thunderbolt capability, cable info, power data, and a live power graph.
The live view tells you what your ports are doing right now. The Flight Recorder runs always-on in the background and records it, so you can catch the intermittent faults that only show up when nobody's looking. It survives restarts and stays light on memory.
Flight Recorder
£4.99 one-time · works on 2 Macs14-day money-back guarantee, no questions asked. Apple Silicon only (M1 and later).
Secure checkout via Stripe. Your licence key is emailed instantly.
Already bought? Your key is in your email. Activate it in the app under Flight Recorder.
WhatPort correlates several IOKit and SMC services per physical port. Everything is read unprivileged: no root access, no entitlements, no background daemon. State updates the moment a device connects or disconnects, and is polled every second as a safety net.
Reads USB-C lane state per PHY: which transport protocol each lane is carrying and whether the lane is powered on.
Reads Thunderbolt link speed, lane width, generation, and port capability. Socket ID maps to physical port number.
Per-port power, split into power in (charging) and power out (to your devices): watts, voltage, current, and the negotiated USB-PD contract.
No. WhatPort reads data from Apple Silicon-specific IOKit services (AppleTypeCPhy, IOPortTransportStateCC) that don't exist on Intel Macs. You need an M1 or later.
Yes. On Macs without a battery (Mac mini, Mac Studio, Mac Pro), WhatPort reads per-port power from the SMC, so power, protocol, and lane data all work the same as on a laptop.
No. All IOKit reads are unprivileged. No entitlements, no System Extension, no background daemon. It runs as a regular menu bar app.
No. There are no analytics, no telemetry, and no network requests. The app reads local IOKit data and nothing else. The source is on GitHub if you want to verify.
One key activates Pro on up to two Macs, so your laptop and your desktop are both covered. Paste the same key into the app on each machine under Flight Recorder. Replacing a Mac? Email support and we'll free up a slot.
WhatCable focuses on cable identity: what a cable can do, its e-marker data, and charging diagnostics. WhatPort focuses on port status: what each port is doing right now, with live lane and power data.
TB5 ports negotiate down to the connected device's capability. If your device only supports TB4, the port runs at TB4 speed. The Thunderbolt section shows both the active link and the port's maximum capability.
When a charger is connected but the battery isn't filling, WhatPort tells you why: it's charging, already full, or being held below full to protect battery health (Optimized Battery Charging or an 80% limit). It only reports a reason it can confirm, never a guess.
WhatPort is signed, notarised, and ready to run. Requires macOS 14 (Sonoma) or later on Apple Silicon.
Grab the latest .zip from GitHub Releases. Unzip and drag WhatPort.app into Applications.
Prefer the terminal? Install with brew and get upgrades for free.
brew install --cask \ darrylmorley/whatport/whatportView the tap