The Best Free Audio to MIDI Converters in 2026
Search for a “free audio to MIDI converter” and you get two kinds of results: tools that are genuinely free, and tools that say free until you hit a sign-up wall, a daily cap, or a watermark on the export. The gap between those matters a lot when all you want is to turn a hummed melody, a bass line, or an MP3 into editable notes you can drop into a project.
This guide skips the marketing. It walks through what makes a free audio-to-MIDI tool actually good, then sorts the real options into categories so you can pick the one that fits how you work. Where we name specific tools, we keep the claims general and honest, because feature lists and pricing change.
What makes a good free audio to MIDI converter
Audio to MIDI is the job of listening to a recording and writing out the notes it hears: pitch, timing, and how long each note lasts. A good converter gets close enough that you spend your time tweaking a few notes rather than redrawing the whole part. A bad one hands you a mess that takes longer to fix than playing it in by hand.
The best tools share a few traits. They are honest about being free. They respect your audio. They handle the kind of material you actually feed them. And they give you output you can open and edit anywhere, not a locked format you have to fight with.
What to look for
Before you commit to any tool, run it through these criteria.
Actually free vs. freemium-gated. “Free” covers a wide range. Some tools are free with no strings. Others gate the useful parts: a forced account before you can export, a daily conversion cap, a length limit, or a watermark stamped on the result. None of those are dealbreakers on their own, but you should know which one you’re signing up for before you upload anything.
Privacy: does it upload your audio or run locally? Many web converters send your file to a server to process it. If your audio is a private demo, an unreleased track, or a client’s stems, that’s worth caring about. Tools that run the conversion locally in your browser never send the file anywhere, which is both more private and usually faster, since there’s no upload wait.
Polyphonic vs. monophonic. Monophonic tools handle one note at a time, which is fine for a solo vocal, a bass line, or a lead. Polyphonic tools handle chords and overlapping notes, which you need for piano, guitar, or anything with harmony. If you try to run a chord through a monophonic tool, it will pick one note and drop the rest.
Supported formats. Check that it reads what you have. MP3 and WAV are table stakes; FLAC, M4A, and OGG are common enough that you’ll want them too.
Output quality and editability. The output should be a standard .mid file that opens in any DAW or notation app. Bonus points for a piano-roll preview so you can see the result before exporting, and for detection settings that let you tune sensitivity for tricky material.
Ease of use. The fastest path is drag a file in, get notes out. The more clicks, accounts, and configuration screens between you and the export, the more friction.
The options, by category
There’s no single “best” tool, because the right pick depends on whether you already own a DAW, how private your audio is, and how much you want to tinker. Here are the main categories.
Browser-based tools that run locally
This is the sweet spot for most people: open a web page, drop in audio, get a MIDI file, no install. The key thing to check is whether the tool processes locally or uploads to a server.
Sound to MIDI, this site, runs entirely in your browser. Your audio is never uploaded; the whole conversion happens on your own machine. It’s free with no sign-up, no daily limit, and no watermark, and it’s polyphonic, so it handles chords and multiple instruments, not just single notes. Under the hood it uses Spotify’s open-source Basic Pitch model running through TensorFlow.js. It reads MP3, WAV, FLAC, M4A, and OGG, outputs a standard .mid, and gives you a piano-roll preview plus advanced detection settings to dial in tricky parts. If you specifically have an MP3, the MP3 to MIDI page is the same engine pointed at that workflow. For a step-by-step, see how to convert audio to MIDI.
Spotify’s Basic Pitch
It’s worth knowing the model itself. Basic Pitch is Spotify’s genuinely open-source, free pitch-detection model. It’s polyphonic and instrument-agnostic, meaning it isn’t tuned for one sound, and it’s the engine powering a lot of audio-to-MIDI tools today, including this site. Spotify hosts a simple demo page, and developers can run the open-source library directly. If you’re a tinkerer, the library is a great building block. If you just want notes out without touching code, a tool built on top of it (like this site) is the friendlier path.
DAW built-in audio to MIDI
If you already own a DAW, you may not need a separate tool at all. Several DAWs include audio-to-MIDI features, and apps like Ableton Live and Logic Pro have their own conversion functions built in. The upside is that it lives where you’re already working and ties into your instruments. The downside is that these features vary by app and version, and they’re only “free” in the sense that you already paid for the DAW. For a quick one-off, a browser tool is usually faster than booting up a full session.
Dedicated desktop apps for power users
There’s also a category of dedicated desktop transcription software aimed at serious transcribers and producers. These tend to offer fine-grained control, batch processing, and specialized editing, and the more capable ones are typically paid. We won’t quote prices or feature lists here, because they change and vary by product. The takeaway: if audio-to-MIDI is a daily part of your job and you need deep editing control, this category is worth a look. For occasional use, it’s overkill.
How the categories compare
| Criteria | Browser, local (this site) | Basic Pitch (DIY) | DAW built-in | Dedicated desktop |
|---|---|---|---|---|
| Cost | Free | Free / open source | Comes with your DAW | Often paid |
| Sign-up required | No | No | No (DAW account) | Varies |
| Privacy | Runs locally, no upload | Runs locally | Local | Local |
| Polyphonic | Yes | Yes | Usually | Usually |
| Install needed | No | Yes (or demo page) | Yes (the DAW) | Yes |
| Best for | Quick, private conversions | Developers, custom pipelines | People already in a DAW | Heavy, frequent transcription |
An honest note on accuracy
No free audio to MIDI converter is magic, and neither are the paid ones. They all do their best work on clean, isolated parts: a single vocal, a solo instrument, a clear bass line. Feed any of them a dense full mix, with drums, bass, vocals, and synths layered together, and the result gets messy. The model has to guess which of many overlapping sounds you meant, and it will get some of them wrong.
The practical fix is to give the tool the cleanest source you can. If you have stems, use them. If you’re transcribing your own playing, record the part alone. Then expect to clean up the output in your DAW or notation app afterward. Treat the MIDI as a strong first draft, not a finished score. If you want the background on why this is hard, what is audio to MIDI explains how the conversion actually works.
Recommendation and how to choose
For most people, a browser-based tool that runs locally is the best free audio to MIDI converter, because it’s instant, private, and free without the freemium traps. That’s exactly what Sound to MIDI is built to be: no account, no upload, no caps, polyphonic, and a standard .mid out that opens in Ableton, FL Studio, Logic, GarageBand, and MuseScore.
Quick way to decide:
- You want fast, private, zero-hassle conversions. Use a local browser tool like this one.
- You’re a developer building your own workflow. Start from Spotify’s open-source Basic Pitch.
- You live in a DAW and need it once in a while. Try your DAW’s built-in audio-to-MIDI first.
- You transcribe constantly and need deep editing. Look at dedicated desktop software, knowing the strong options are usually paid.
Whichever you pick, the rule is the same: start with the cleanest audio you can, expect to do a little editing, and you’ll get usable MIDI without paying for it.