Ableton Extensions, explained

Ableton Extensions are small add-on tools, introduced in Live 12.4.5, that you trigger from a right-click and that read or edit your Set — tracks, clips, MIDI, tempo, structure — then hand back a result. They're built with a free, open JavaScript SDK, they run in Live 12 Suite Beta only, and anyone who can clearly describe what they want can build one, with or without programming experience.

This guide covers what Extensions actually are, what they can't do (and why that's Max for Live's job instead), how to install and run one, and two ways to build your own: by hand with Ableton's SDK, or with Tunesfork Build, which turns a plain-English description into an installable Extension automatically.

What you need

If you're on Standard, Intro or Lite, Extensions simply aren't available — there's no beta enrollment that unlocks them without Suite.

What Extensions actually are

An Extension is a small tool that runs once: you trigger it, it makes a change or returns a result, then it stops. It isn't a persistent panel, a background process, or a device sitting in a chain. Ableton's own framing is blunt about the scope: Extensions can

• transform MIDI data
• analyze the structure of a song or track
• automate repetitive tasks
• create unusual generative patterns
• connect Live to external services
• and, per Ableton's own Extensions FAQ, "even play games in Live"

They're built on Node.js, run as a separate process alongside Live, and are triggered from the right-click context menu on a compatible element — a track, a MIDI or audio clip, and so on.

What Extensions can't do

This is the part worth getting right before you have an idea and hit a wall. Extensions are explicitly not for anything continuous, real-time, or sample-accurate:

• No real-time audio processing — no effects, synthesis or filtering during playback
• No real-time MIDI processing or monitoring during playback or recording
• No devices in the signal chain — no synths, samplers or audio effects
• No background processing while transport is running
• No sample-accurate or event-accurate performance timing
• No live interaction with the transport or playhead position

That's what Max for Live is for. Ableton's own FAQ draws the line clearly: Max for Live is a patching environment for synthesis, custom instruments and complex signal chains; Extensions are JavaScript tools that act on the Set itself — its structure, its data, its workflow. One doesn't replace the other; a real-time performance tool still belongs in Max for Live, and a one-shot workflow tool is what Extensions are for.

Installing and running an Extension

1. Install it. In Live, go to Settings → Extensions and add the Extension file.
2. Right-click a compatible element in your Set — a MIDI clip, an audio clip, a track, or whatever the Extension targets.
3. Check the context menu. If the Extension supports the element you selected, its name appears there. If you don't see it, that usually means the Extension doesn't apply to that particular element type — not every Extension works on every element.
4. Click its name. A dialog lets you adjust its parameters before it runs.
5. It runs once — makes the change or returns the result — then stops. There's nothing left running in the background afterward.

Once installed, an Extension is available across every Set you open in Live Suite 12.4.5 or later, not just the project you installed it from.

Building an Extension by hand

Ableton's own path, laid out in their launch announcement: download the free Extensions SDK, install Node.js v24.16.0 or later, and write JavaScript against the SDK's APIs for reading and editing tracks, clips, MIDI and devices. It's under 5 MB, free, and — per Ableton's own FAQ — doesn't require prior programming experience if you can describe what you want clearly enough for an AI coding assistant to help, since the SDK is built on standard web technologies. Ableton's launch video puts it plainly: "if you've worked with web technologies, you're already halfway there. If not, you can borrow from existing code, use other tools to fill the gaps."

Building an Extension with Tunesfork Build

Tunesfork Build skips the setup entirely. Describe what you want in plain English — "Humanize selected MIDI notes," "Rename tracks from clip names," "When I right-click a MIDI clip, humanize its note velocities and timing" — and it:

1. Plans it. An AI turns your description into a build plan: the target element (a MIDI clip, audio clip, track, or scene), the capabilities, parameters and how you'll interact with it. You review and can revise the plan before anything is built.
2. Generates it. Once you approve, it writes real TypeScript against the official @ableton-extensions/sdk 1.0.0 API, validates and compiles the result, and repairs anything that fails a check.
3. Packages it. You get a downloadable .ablx — install it the same way as any other Extension, from Live → Settings → Extensions — plus an editable source .zip if you want to keep tweaking it by hand.

Every project is saved to your account, so you can reopen and iterate on an Extension later rather than starting over. It's free to start, with a $5 AI usage allowance on the beta; TunesFork's paid plans lift that cap if you're building more.

One thing Tunesfork Build can't do for you: Ableton's own SDK and CLI downloads are part of their beta program and can't be redistributed, so if you want to build and test the generated source project yourself (most people just install the .ablx and skip this), you'll still need your own Ableton beta SDK download alongside Live 12.4.5 Suite Beta with Extensions Developer Mode enabled.

Where to find and share Extensions

Ableton's Discord server is the hub for both sides of this: #extensions for using and discussing Extensions with other producers, #extensions-sdk for build questions, and #extensions-gallery for browsing and sharing what people have made. Since Extensions aren't made by Ableton, if you run into a problem using one, the Extension's own developer is who to ask — not Ableton support.

A word on safety: Extensions run on Node.js, a runtime separate from Live itself, which is exactly what makes them powerful and exactly why the usual caution applies. Treat a downloaded Extension the way you'd treat any other downloaded software, and only install ones from sources you trust.

Frequently asked questions

What Live edition do I need for Extensions?

Live 12 Suite, on the 12.4.5 or later beta. Extensions aren't available in Standard, Intro or Lite, and there's no beta enrollment path that unlocks them without a Suite license.

Do I need to know how to code to build an Extension?

Not necessarily. Ableton's own FAQ says the SDK is built on standard web technologies that AI coding assistants handle well — if you can clearly describe the Extension you want, you can get a working one built with AI help. Tunesfork Build is built around exactly this: describe the idea, approve a plan, and it writes and packages the code for you.

What's the difference between an Extension and a Max for Live device?

An Extension runs once, triggered from a right-click, to read or change your Set's structure and data — tracks, clips, MIDI, tempo. A Max for Live device is a persistent, real-time patching environment for synthesis, instruments and signal chains. If what you want happens continuously during playback, it belongs in Max for Live, not an Extension.

How do I install an Ableton Extension?

Go to Live → Settings → Extensions and add the file. To use it, right-click a compatible element in your Set (a track, MIDI clip or audio clip); if the Extension applies to that element, its name shows up in the context menu.

Why doesn't my Extension show up when I right-click?

Most Extensions are built for a specific element type — a MIDI clip, an audio clip, a track. If the Extension doesn't support whatever you right-clicked, it won't appear in that menu. Try right-clicking the element type the Extension was actually built for.

Can Extensions process audio in real time?

No. Extensions run once and stop — they can't do real-time audio or MIDI processing, can't act as devices in a signal chain, and can't do anything that needs sample-accurate timing during playback. That's what Max for Live is for.

Is the Extensions SDK free?

Yes, the SDK itself is free and under 5 MB. Individual third-party Extensions may be free or paid, at their own developer's discretion — that's separate from the SDK.