MP3 to MIDI conversion analyzes audio files and extracts musical notes, timing, and velocity into standard MIDI format. Unlike MP3 or WAV files that store sound waves, MIDI files contain musical instructions — which notes to play, when, and how loud. This makes them fully editable in any digital audio workstation.

Our converter uses Spotify's Basic Pitch neural network to detect pitch, onset, and velocity from any audio source — vocals, guitar, piano, or full mix. The conversion runs entirely in your browser using TensorFlow.js, so your files never leave your device.

Whether you need an AI MIDI converter for vocal melodies, piano recordings, or full mixes, our audio to MIDI tool delivers accurate results.

Audio Analysis Tools

Modern audio analysis relies on digital signal processing techniques like Fast Fourier Transform (FFT), chroma feature extraction, and onset detection. These algorithms decompose audio into frequency components to identify tempo, key, chords, and more.

Most analysis tools run locally using browser audio APIs. The Stem Splitter is different: it uploads audio to a configured model backend so it can produce real separated stems instead of EQ-filtered tracks. Whether you're a DJ preparing a set, a producer sampling a track, or a student analyzing music, each tool states its processing boundary clearly.

Complete Music Toolkit

From audio recording to finished production, mp3tomidi covers every step. Convert audio to MIDI for editing, detect BPM and key for beatmatching, identify chord progressions for transcription, separate stems for remixing, render MIDI to audio with different instruments, and generate printable sheet music.

All tools work in your browser with no software installation. Free forever for core features.

How It Works

Step 1

Upload Your Audio

Upload any MP3, WAV, OGG, or FLAC file.

Step 2

AI Analyzes in Browser

Our algorithms process your audio privately.

Step 3

Get Instant Results

View BPM, key, and more.

100% PrivateAudio never leaves your browser

No SignupStart using tools immediately

Instant ResultsAnalysis completes in seconds

Free ForeverCore tools always free

See It In Action

Upload any audio file and instantly see BPM, key, chord progression, and detected notes. Our bpm finder and audio separator tools work together to give you a complete analysis in seconds.

Input

sample-track.mp3

3.2 MB · MP3 · 0:45

Output

128BPM

A Minor

Chord Progression

AmFCGAm

847 notes detected

Confidence94%

Why Choose mp3tomidi?

Built for privacy, speed, and accuracy.

100% Browser-Based

Your audio never leaves your device. All processing happens locally.

No Signup Required

Start analyzing immediately. No account needed for basic tools.

Instant Results

Get BPM, key, and chord results in seconds, not minutes.

Multiple Formats

Supports MP3, WAV, OGG, FLAC, M4A, AAC, and WebM.

Professional Accuracy

Algorithms tuned for accuracy comparable to professional tools.

Free to Use

Basic analysis tools are completely free, forever.

Trusted by Musicians Worldwide

“I use the BPM detection before every gig. It's faster than any desktop software I've tried, and I love that everything runs in my browser.”

Sarah M.

DJ & Producer, Berlin

“Converting my guitar recordings to MIDI changed my workflow completely. I can layer synths on top of acoustic ideas without manually programming notes.”

Mike C.

Music Producer, Los Angeles

“The chord detection tool saves me hours of transcription work every week. My students can see the chord progression of any song instantly.”

Lisa P.

Music Educator, London

“As a game developer, I need MIDI files for dynamic soundtracks. This tool lets me convert reference tracks into editable MIDI in seconds — no DAW required.”

Tom H.

Game Developer, San Francisco

“The stem splitter is surprisingly good for a free browser tool. I use it to quickly isolate vocals before remixing. Saves me so much setup time.”

DJ Pulse

Remixer, Amsterdam

“I record piano improvisations and convert them to sheet music. The MusicXML export works perfectly with MuseScore. Absolutely brilliant for a free tool.”

Maria S.

Piano Student, São Paulo

About mp3tomidi

mp3tomidi was built by musicians, for musicians. We believe that powerful audio tools should be accessible to everyone — not locked behind expensive software licenses or cloud subscriptions. That's why every tool on this site runs entirely in your browser, using cutting-edge web technologies like the Web Audio API, TensorFlow.js, and WebAssembly.

Our core conversion engine uses Spotify's open-source Basic Pitch model, a neural network trained on thousands of hours of music to accurately detect pitch, timing, and dynamics. Combined with our custom post-processing pipeline (quantization, noise filtering, overlap merging), you get MIDI output that's ready for professional use in any DAW.

Privacy is not optional — it's foundational. Your audio files are never uploaded to our servers. All analysis, conversion, and processing happens locally in your browser. We don't track what you upload, we don't store your audio, and we don't use your data for model training. What happens in your browser stays in your browser.

Whether you're converting a vocal melody to MIDI, detecting the key of a reference track, splitting a song into stems for remixing, or generating sheet music from a performance — mp3tomidi is your free, privacy-first music toolkit.

Frequently Asked Questions

What is MP3 to MIDI conversion?

MP3 to MIDI conversion analyzes an audio file and extracts the musical notes, timing, and dynamics into the standard MIDI format. Unlike audio files that store sound waves, MIDI files store editable musical instructions — making it easy to change notes, tempo, and instrument sounds in any digital audio workstation.

Is mp3tomidi really free?

Yes. All core tools including BPM detection, key detection, chord analysis, and MP3 to MIDI conversion are completely free to use. No signup, no credit card, no hidden fees. No signup or account creation is needed. Just visit any tool page — whether it's the BPM finder, chord detector, stem splitter, or MIDI to sheet music converter — and start using it immediately.

What audio formats are supported?

mp3tomidi supports MP3, WAV, OGG, FLAC, M4A, AAC, and WebM audio files up to 50 MB. Simply drag and drop or click to upload — no conversion needed before analysis. The converted MIDI files are compatible with all major DAWs including GarageBand, Ableton Live, FL Studio, and Logic Pro.

How accurate is the BPM detection?

Our BPM detection is accurate within 1–2 BPM for tracks with a steady tempo. Each result includes a confidence score so you know how reliable the reading is. Complex or tempo-changing tracks may show lower confidence values.

Is my audio uploaded to a server?

Most analysis and MIDI tools run in your browser. The Stem Splitter uploads audio to a separate Python model backend because real AI source separation cannot run inside Cloudflare Pages. Each tool page states its processing boundary before use.

Can I use the output in GarageBand or Ableton?

Yes. All MIDI files are exported as standard MIDI Type 0, which is compatible with every major DAW including GarageBand, Ableton Live, Logic Pro, FL Studio, and more.

Do I need to install anything?

No installation required. mp3tomidi works entirely in your web browser — Chrome, Firefox, Safari, and Edge are all supported. Just visit the site and start using the tools.

How does this compare to desktop software?

mp3tomidi delivers accuracy comparable to desktop alternatives at zero cost, with no installation required. The key advantage is complete privacy — your audio never leaves your device — plus instant access from any browser on any operating system.

Ready to analyze your audio?

Detect BPM, musical key, and more — all in your browser, completely free.

Try BPM & Key Detection