IORegistryExplorer

Note

This is a utility tool, NOT a kext. It does not need to be installed in your EFI.

IORegistryExplorer is a macOS utility for viewing the I/O Registry — the hierarchical tree of all hardware devices, drivers, and their relationships in macOS. It’s essential for debugging hardware issues, verifying kext loading, and understanding device paths.

Overview

The macOS I/O Registry is a dynamic database that tracks all hardware devices and their associated drivers. IORegistryExplorer provides a graphical interface for browsing this tree, making it much easier to understand than the command-line ioreg tool.

Features

Tree View: Browse the I/O Registry in a hierarchical tree structure
Search: Search for specific devices, classes, or properties
Property Inspector: View detailed properties for any I/O Registry entry
Class Browser: Filter by IOService class
Export: Save I/O Registry snapshots for sharing and analysis

Installation

Download from GitHub
Open the downloaded DMG file
Drag IORegistryExplorer to your Applications folder

Alternative: Apple’s Version

IORegistryExplorer is also available as part of the Additional Tools for Xcode package from Apple Developer Downloads (requires a free Apple Developer account). The open-source version on GitHub provides the same functionality.

Usage

Launch IORegistryExplorer
Browse the I/O Registry tree to find your hardware devices
Click on any entry to view its properties in the inspector panel
Use the search bar to find specific devices or classes

Common Use Cases

Verify kext loading: Search for a kext name to confirm it’s loaded and attached to the correct device
Find device paths: Determine the ACPI path for a device (needed for some SSDTs)
Debug hardware: Check if a device is recognized and has the correct properties
Check sensor data: Verify VirtualSMC sensor plugins are providing data

FAQ