MP3toMIDI is a free, browser-based AI converter that turns MP3, WAV, FLAC, and other audio files into editable MIDI files without uploading your audio to a server.
What is MP3toMIDI?
MP3toMIDI is an AI-powered online audio-to-MIDI conversion platform designed for musicians, producers, composers, educators, and music creators. It takes audio input in MP3, WAV, OGG, FLAC, M4A, AAC, or WebM formats and outputs standard MIDI files compatible with major DAWs such as Ableton Live, FL Studio, Logic Pro, Cubase, and GarageBand. The conversion runs entirely in the browser using TensorFlow.js and Spotify's open-source Basic Pitch neural network, so your audio never gets uploaded to a server.
Key Features
MP3toMIDI bundles six audio tools into a single browser-based workspace, each with a distinct processing boundary stated on its page.
- AI audio-to-MIDI conversion — Converts any audio source (vocal, guitar, piano, full mix) into standard MIDI files using Spotify's Basic Pitch model for pitch, onset, and velocity detection.
- BPM and key detection — Instantly identifies tempo and musical key from an uploaded audio file, with confidence scores for each reading.
- Chord detection — Automatically detects chord progressions from audio files, saving hours of transcription work.
- Stem splitter — Separates a track into music, vocal, bass, and drums stems using a Python model backend (the only tool that uploads audio).
- MIDI to audio rendering — Exports MIDI files as MP3, WAV, FLAC, OGG, M4A, WEBM, AIFF, WMA, or ALAC audio with your choice of instruments.
- MIDI to sheet music — Converts MIDI files to printable sheet music and MusicXML for use in notation software like MuseScore.
- 100% private by default — Analysis tools process audio locally in your browser; no account, signup, or installation is required.
Who is it for?
MP3toMIDI serves anyone who works with music digitally, from DJs to game developers.
- Musicians and producers — Convert recorded instruments or vocals into editable MIDI for layering synths, remixing, or fixing timing without reprogramming notes.
- DJs — Use BPM and key detection before gigs to match beats and harmonic mixes faster than desktop software.
- Music educators — Extract chord progressions and sheet music from any song for classroom transcription and analysis.
- Game developers and content creators — Turn reference tracks into editable MIDI for dynamic soundtracks or generate stems for remixes, all without installing a DAW.
What can you do with MP3toMIDI?
- Transcribe melodies: Upload a vocal or piano recording and download a MIDI file that captures the notes, timing, and velocity.
- Detect BPM and key: Quickly find the tempo and key of any track to prepare DJ sets or match samples.
- Separate stems: Isolate vocals, drums, bass, and music for remixing, karaoke, or sampling.
- Generate sheet music: Create printable sheet music or MusicXML from your MIDI performances for notation software.
How does MP3toMIDI work?
MP3toMIDI processes audio locally in your browser. Upload an audio file (MP3, WAV, OGG, FLAC, or M4A up to 50 MB), and the AI analyzes it using Fast Fourier Transform and chroma feature extraction to identify pitch, tempo, key, and chords. Once analysis completes, you get a downloadable MIDI file. The Stem Splitter is the exception: it uploads your file to a separate model backend to produce real separated stems instead of simple EQ filtering.
Pricing
MP3toMIDI is free to use. All core tools — BPM detection, key detection, chord analysis, and audio-to-MIDI conversion — are free forever, with no signup or credit card required.
FAQ
Is MP3toMIDI really free?
Yes. All core tools are free to use with no signup, no credit card, and no hidden fees. Just visit any tool page and start analyzing audio instantly.
What audio formats are supported?
MP3, WAV, OGG, FLAC, M4A, AAC, and WebM files up to 50 MB are supported. You can drag and drop or click to upload — no format conversion is needed before analysis.
Is my audio uploaded to a server?
For most tools, no. BPM detection, key detection, chord analysis, and audio-to-MIDI conversion run entirely in your browser. The Stem Splitter is the exception — it uploads audio to a Python model backend because true AI source separation cannot run inside Cloudflare Pages.
Can I use the exported MIDI in my DAW?
Yes. All MIDI files are exported as standard MIDI Type 0, compatible with GarageBand, Ableton Live, Logic Pro, FL Studio, Cubase, and other major DAWs.
How accurate is BPM detection?
BPM detection is accurate within 1–2 BPM for tracks with a steady tempo, and each result includes a confidence score. Tempo-changing or complex tracks may return lower confidence values.
