This comparison helps you choose a free audio-to-MIDI workflow by its input, downloadable output, privacy and editing limits. Transcription estimates notes rather than simply changing a file extension. “Free” should cover the file you need, not just a preview; no option here is a guaranteed accuracy winner.
A free audio-to-MIDI workflow must let you save editable notes, not just hear a preview. Start with the recording you have: one exposed melody, piano chords or a full mix. Those are different transcription problems, and a tool that works for one may struggle with another.
We publish SoundToMIDI. The options below describe workflows and documented capabilities; they are not an independent accuracy ranking.
Which free transcription route should I use?
For one recording, SoundToMIDI provides local browser transcription and an unlimited free Raw MIDI download without an account. Choose a short, exposed phrase, convert it, listen to the notes and save the .mid. Editing controls and previews are available before purchase; the optional Music Export Pack pays for additional export files, not a more accurate recognition model. Project backups and cloud AI arrangements are separate features.
For an installable, scriptable route, Spotify Basic Pitch provides a local Python package. For a score, convert the recording to MIDI first, then follow the MuseScore import and notation workflow. A notation editor that opens MIDI is not necessarily an audio transcription tool.
Can I convert a folder for free without losing fidelity?
SoundToMIDI processes one selected recording at a time; it does not offer a folder batch queue. Unlimited free conversions do not mean simultaneous batch processing. For a folder of piano recordings, Melodfy’s official page documents a local folder queue and a piano-specific model. That is a documented alternative, not a head-to-head quality test by us. For scripted jobs, use the Basic Pitch setup and batch preparation guide.
MIDI cannot preserve an audio recording’s original tone. Judge transcription by correct pitches, note starts and lengths, and the time needed to fix mistakes. Test a few representative files before running a folder. For the quality-versus-speed decision, use the comparison worksheet.
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. Local conversion can process audio without uploading it. Check cloud-save options separately: at SoundToMIDI, original audio is uploaded only if you select audio backup.
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 conversion in your browser without uploading audio. Optional audio backup requires your explicit selection. Conversion and Raw MIDI downloads are free without sign-up, a daily limit or a watermark; edited exports are a separate option. It can estimate overlapping notes and chords, but does not reliably separate instruments in a mixed recording. 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 one-off file, a browser tool avoids opening a DAW session; actual processing and correction time still need checking.
How the categories compare
| Criteria | Browser, local (this site) | Basic Pitch (DIY) | DAW built-in | Dedicated desktop |
|---|---|---|---|---|
| Cost | Conversion and Raw MIDI free; edited exports optional | Free / open source | Comes with your DAW | Often paid |
| Sign-up required | No for Raw MIDI or guest pack purchase; yes for account saves | No | Depends on the DAW license | Varies |
| Processing | Local conversion; optional cloud features separate | Local Python workflow | Check the feature | Check the product |
| Overlapping notes | Estimates them; no reliable instrument separation | Supported, best with one instrument | Depends on the feature | Depends on the product |
| 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 |
Compare one recording before choosing
Use the same short recording in each tool and keep the original alongside the MIDI. Count missed notes and extra notes separately, check a few note starts, and listen after assigning the same instrument. A larger note count is not necessarily a better result. Time the corrections too: the useful result is the one you can finish editing.
The recording comparison worksheet walks through that check. For a known input and a visible mistake, listen to the original MP3, Raw MIDI playback and a manual correction. These are examples from this tool, not a head-to-head accuracy ranking.
An honest note on accuracy
To check a result before choosing a tool, try our eight-second melody, then download the free Raw MIDI. The worked examples include the source notes, actual output, and extra notes the model detected. They use synthesized test clips; your own recording may behave differently.
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.
Continue with your recording
For a free browser walkthrough, use how to convert audio to MIDI. For an installable workflow, check the software guide. For a known input and a visible transcription mistake, compare our original MP3 and actual MIDI result before trying a recording of your own.