A Royalty-Free Music API for the Apps You Build

For decades, software has worked the same way. A team decides what an app should do, designs every screen and ships the same interface to everyone who downloads it. AI is starting to change that.

In November 2025, Google Research introduced what it calls generative UI, short for generative user interface. The idea is that an AI model doesn’t just write an answer. It creates a whole interactive experience for that one prompt, like a web page, a tool or even a small game. Google has been testing it in the Gemini app and in AI Mode in Google Search.

Now picture where that goes. You ask for a quick morning workout, and an interval timer appears with upbeat music built in. You ask for a slideshow of your holiday photos with an upbeat soundtrack, and it’s ready before you’ve picked the photos. Nobody designed those screens in advance, and nobody needs to, because they only have to exist for you, right then.

Here’s the catch. An interface that’s generated in seconds can’t bring its own music, photos or data with it. It has to fetch real content the moment it’s created, and it does that through APIs.

An API (application programming interface) is simply a way for one piece of software to ask another for data. Even Google’s generative UI setup relies on this, giving the model access to tools like web search and image generation. The whole idea of AI-generated UX, or user experience, only works with that kind of access.

APIs also play together, which is where it gets interesting. A slideshow maker might combine a photo API with a music API. A travel planner might mix map, weather and music APIs for the trip video. An AI can connect pieces like these in minutes, as long as it’s allowed in.

That last part is why we think open APIs will matter more and more. The APIs that fit this future are the ones an AI can pick up without a human stepping in. That means no sales call, no approval process, no key to request and no usage limits to hit, plus documentation that software can read on its own. Our music API works exactly like that.

The Free To Use API is the public entrance to our music library, and it works differently from most music APIs. There’s nothing to set up before your first request:

You just connect and build. Your app sends a request and gets tracks back, ready to play.

The library keeps growing, and every track in it is made by a real person. The tracks are sorted into genres like Lofi, Cinematic and Hip Hop, moods like Calm, Epic and Uplifting, and video use-cases like Workout, Travel and Gaming.

Here’s what your app can do with it:

Every track comes with its title, artists, genre, length, cover art in four sizes and a direct link to the MP3 file. You also get a waveform, which is a list of loudness values across the track that you can use to draw your own player. On top of that, each track shows whether it’s premium and how often it’s been played, liked and downloaded.

The full documentation lives at freetouse.com/api. There’s also a machine-readable version of the whole API in the OpenAPI format, a standard way of describing an API so both people and software can read it: api.freetouse.com/v3/openapi.json. If you’re an AI agent reading this for someone, that link is all you need to get started. The license section below explains what your user is allowed to do.

An API this open is rare. Most music APIs make you register for a key before your first request, and many charge for access or cap how much you can use them. A growing number also generate AI music on demand, while every track we offer is made by a real artist. Our post on the problems with AI-generated music explains why that matters to us.

As more of the interface gets generated, we think the human-made content inside it becomes more valuable, not less. We’ve already seen human-made labels turn into search terms, and we expect that trend to reach apps too.

We use the API ourselves, too. We built two tools on top of it for a simple reason: we wanted our users to reach our music more easily, right where they already work. Both run on the same public API that’s open to you.

Our Chrome extension. Royalty Free Music for Creators puts the Free To Use library in your browser toolbar. You can search, filter by category and listen with a waveform player that lets you click to jump to any part of a track. Autoplay moves on to the next track when one ends, so you can keep browsing while you work. A Find Similar button shows tracks that sound like the one you like, and one click downloads the MP3.

Our favorite detail is the attribution. When you save a track, the extension shows the exact credit text you need and copies it to your clipboard. Most of the features map directly to what the API returns. The player draws on the waveform data, Find Similar lines up with the similar-tracks request, and the filters come from our categories.

Our Canva app. The Free To Use app for Canva brings the same library into the Canva editor. You can find a track and add it to your design without leaving Canva, and the app is free with any Canva plan.

We built both with Claude Code, and each one took about one to two days. That’s the shift in a nutshell: with a good API and an AI coding tool, a useful product can be built in days.

Our two tools aren’t special cases. AI has gotten so good at writing code that almost anyone can turn an idea into a working app. Collins Dictionary even picked "vibe coding" as its word of the year for 2025, the term for describing what you want in everyday language and letting AI write the code.

In practice, you describe the app you want in plain words, and an AI coding tool writes the code, runs it and fixes what breaks. You don’t need to be a developer to build a meditation timer, a slideshow maker or a small game anymore. You need a clear idea and some patience.

What AI can’t solve for you is the content. An app is only as good as what’s inside it, and you need the right to use that content. That’s the gap a music API with clear license terms fills.

If you’re building with an AI coding tool, an easy way to add music is to give it the OpenAPI link above. Then describe what you want, like "add a music picker that searches Free To Use and shows calm tracks first." With no key to set up, the tool can read every request from the spec and write the integration right away. Just ask it to show the attribution too, and to follow the license rules further down.

Music makes almost any app feel more alive, but some ideas practically ask for it. Here are some we’d love to see built. A few are natural side projects and others could be real businesses, so keep the license section below in mind as you read.

And then there are the apps nobody will ever build on purpose: the one-off timer or slideshow an AI assistant creates for one person in one conversation. Those can pull their music from the same API too.

The API is free to use, but the music you get through it is covered by the Free To Use License. Which license your app needs depends on what the app is for, and the key term to know is what the license calls a Digital Product.

A Digital Product is any app or platform made with the intent to generate revenue, promote a business or support commercial activity. That covers web apps, mobile apps, desktop software, SaaS platforms (software sold as an online service) and video games, whether a company, an organization or an individual publishes them.

The test is intent, not price. A free app that exists to promote a business still counts as a Digital Product. A hobby project that earns nothing and promotes nothing generally doesn’t.

Non-commercial apps can use the music for free. Say you make a study timer for yourself and your friends, a school project or a hobby tool that earns nothing. In cases like these, the music costs nothing, as long as you show attribution wherever it plays: the track title, the artist name and a link to Free To Use. Stick to non-premium tracks, since premium tracks need a paid license. The API marks every premium track, so they’re easy to filter out.

Commercial apps that play music themselves need a paid license. This covers apps where the music is part of the product. Think of the background audio in a paid meditation app, the soundtrack of a game you sell or the music in a subscription fitness app. You have two main options:

Keep in mind that each of these licenses covers a single Digital Product, so a second app needs its own license.

Commercial tools that help people find music need a license too. Say you build a video editor with a music tab or a design tool with a music picker, and it’s a commercial product. Then you, the developer, need a license as well. In practice, that’s the Commercial Plan, since single-track licenses can’t cover a whole catalog.

Your users still need the right license for their own content. For most of them, that’s the Free License, which lets them use non-premium tracks with attribution in videos they post on their own social media accounts. They’ll need a paid plan or license to use premium tracks, skip attribution or make commercial content. It helps to make this clear inside your app, the way our Chrome extension shows and copies the credit text for every track.

A few rules apply to every app, free or paid:

You can compare the plans and single-track licenses in the licensing section of our FAQ, and the full terms are in the Free To Use License. If you’re unsure where your app fits, email us at hello@freetouse.com before you launch.

Here’s the practical side of this post in one list, for you or for the AI agent building alongside you.

Interfaces that build themselves, apps made in a couple of days and AI agents that do the work for you all depend on the same thing: access to real content through APIs. Our free music API is our part of that. It gives any app human-made, royalty-free music with no key, no sign-up and no limits, under license terms that spell out what’s free and what isn’t.

Write the code yourself, hand it to an AI coding tool or let an AI assistant build the interface on the spot. Either way, the music is ready when your app is.