Best MIDI Router for Mac

Last updated: March 2026

Routing MIDI between apps on macOS sounds simple — but the moment you need to filter channels, fan out to multiple destinations, or debug what is actually flowing, basic tools fall short. This guide compares every major MIDI routing option available on Mac, explains what each one does well, and helps you choose the right tool for your setup.

What does a MIDI router do?

A MIDI router sits between a source — a hardware keyboard, a DAW track, a software synth — and one or more destinations. It forwards MIDI data, and optionally filters, transforms, or splits it along the way. On macOS, MIDI devices communicate through MIDI ports. A router creates virtual ports that apps can connect to, and then manages what data flows between them.

Common things people use a MIDI router for:

• Sending a hardware keyboard's output to multiple apps at once
• Routing MIDI between two DAWs that cannot connect directly
• Filtering out unwanted channels or message types before they reach a synth
• Transposing, remapping, or velocity-scaling notes in transit
• Splitting a keyboard into zones that trigger different instruments
• Monitoring exactly what MIDI data is flowing at any point in the chain

Option 1: macOS IAC Driver (built-in)

macOS ships with the IAC (Inter-Application Communication) Driver, a virtual MIDI bus built into Audio MIDI Setup. To enable it: open Audio MIDI Setup, go to Window > Show MIDI Studio, double-click the IAC Driver icon, and check "Device is online".

What it does well:

• Zero cost — it is already on your Mac
• Reliable, low-latency inter-app MIDI transport
• Recognized by every macOS DAW and app

Where it falls short:

• No visual interface — you configure everything by name in each app separately
• No filtering — all data on a port goes everywhere
• No monitoring — you cannot see what is flowing through the bus
• No fan-out — one port goes to all listeners with no per-destination control
• No message transformation — you cannot transpose or remap in transit

Best for: Simple setups where you just need one app to send MIDI to another and do not need filtering or monitoring.

Option 2: MIDI Patchbay

MIDI Patchbay is a free macOS utility that predates modern macOS versions. It provides a table-based routing interface where you define connections between MIDI sources and destinations, with basic filtering options per connection.

What it does well:

• Simple, explicit routing table
• Basic channel filtering and remapping
• Runs as a background process

Where it falls short:

• No longer actively maintained — compatibility issues on recent macOS versions
• No visual patch-graph — connections are rows in a table
• No real-time message monitoring
• Limited processing — no velocity curves, no scripting, no advanced tools
• No session management or quick preset switching

Best for: Users on older macOS who need a lightweight routing table and cannot run modern tools.

Option 3: Bome MIDI Translator Pro

Bome MIDI Translator Pro is a commercial MIDI routing and transformation application with a rule-based scripting system. It is powerful for complex translations — remapping one MIDI event to another, triggering keystrokes from MIDI, or building elaborate conditional logic.

What it does well:

• Very powerful rule-based event translation
• Can trigger keystrokes, mouse events, and system actions from MIDI
• Supports MIDI over network
• Active development and support

Where it falls short:

• Paid software (licence required for full use)
• Steep learning curve — routing requires writing translation rules
• No visual patch-graph — connections are rule lists
• Overkill for users who just need routing and monitoring

Best for: Power users who need MIDI-to-keystroke mapping or complex conditional translation logic and are comfortable with a rule-based workflow.

Option 4: Midilize

Midilize is a macOS MIDI router and monitor built around a visual patch-graph interface. Your entire routing setup appears as nodes and cables on a canvas. Connect a MIDI In node to any combination of processing tools and MIDI Out nodes by dragging cables between them. Changes take effect immediately — no restart, no config files.

What it does well:

• Visual patch-graph routing
• Visual patch-graph — see every connection at a glance
• Real-time MIDI monitor built in — see every message as it flows
• 40+ processing tools: transpose, channel filter, velocity modifier, key mapper, chord generator, arpeggiator, quantizer, and more
• JavaScript and Lua scripting for custom logic
• Virtual port management — create named ports without touching Audio MIDI Setup
• Session files — save and load your entire routing setup instantly
• Runs silently in the background with minimal CPU use

Where it falls short:

• Does not support MIDI-to-keystroke translation (that is Bome's territory)
• Requires macOS 14 Sonoma or later

Best for: Musicians, producers, and developers who want visual MIDI routing with real-time monitoring and processing on modern macOS.

Comparison table

How to set up visual MIDI routing with Midilize

Getting started takes less than a minute:

Example: keyboard to two DAWs with channel split

A common live performance setup: one keyboard controlling two DAWs, with the low register going to a bass synth and the high register to a lead synth.

1. Add a MIDI In node — select your keyboard
2. Add a Split node — configure split point at C4
3. Add two MIDI Out nodes — one for each DAW's virtual input
4. Connect: Keyboard → Split → DAW 1 (low) and DAW 2 (high)

The entire routing is visible on the canvas. In Monitor Mode you can verify both paths are receiving correctly before going on stage.

Why the IAC driver alone is not enough

The IAC Driver moves data between apps reliably — but it gives you no visibility and no control over that data. If a MIDI message is going to the wrong destination, the IAC driver offers no way to see or fix it without reconfiguring every app individually. There is no way to know if data is flowing at all without a separate monitoring tool.

Midilize keeps the IAC driver's reliability — it uses the same CoreMIDI framework under the hood — while adding the visual layer that makes routing setups actually manageable. You can also bypass the IAC driver entirely by using Midilize's own virtual ports, which appear in other apps just like IAC ports but are named and managed from one place.

Frequently asked questions