MP3toMIDI.io
MP3toMIDI.io is a free, browser-based tool that converts MP3 audio files into standard MIDI files using a lightweight machine learning model. Unlike simple format conversion, it performs automatic music transcription, detecting note onsets, pitches, durations, velocities, and pitch bends from audio and encoding them as MIDI events. Processing happens entirely on the user's device, ensuring audio privacy without requiring signup or software installation. The converter accepts MP3 files up to 20 MB and 3 minutes in length, and users can select a preset audio type (voice, piano, guitar, etc.) to optimize detection accuracy. It supports polyphonic input, meaning it can recognize multiple simultaneous pitches, but it does not perform stem separation; for best results, clean solo instrument or vocal recordings are recommended over dense full-band mixes. After transcription, users can preview the synthesized MIDI alongside the original audio, and edit notes directly in a built-in piano roll editor. The interface allows moving, resizing, joining, or deleting notes, with undo/redo and optional grid snapping. Once satisfied, users can download the MIDI file for further editing in digital audio workstations (DAWs) or other MIDI-compatible software. The tool runs in modern web browsers on desktop or mobile devices, with performance dependent on audio length and hardware. It is particularly useful for musicians, producers, and hobbyists who need a quick, accessible way to extract note data from audio recordings without complex software setups.
- Category
- Music Audio
- Pricing
- Free
Problem solved
MP3toMIDI.io solves the problem of converting audio recordings into editable MIDI notation without requiring expensive software or technical expertise. It enables users to quickly extract note information from MP3 files for use in music production, transcription, or learning purposes, all within a privacy-preserving browser environment.
Use cases
- Transcribing a melody from a vocal recording
- Extracting piano chords to MIDI for remixing
- Creating a MIDI sketch from a guitar riff
- Analyzing a bass line for educational purposes
- Converting a hummed tune into notation
Audience
- Content Creators
- Hobbyists
Pros
- No account or software installation required
- Audio processing is done locally for privacy
- Built-in MIDI note editor with undo/redo
- Polyphonic note detection
- Standard MIDI file output
Cons
- Limited to 20 MB and 3 minutes MP3 files
- Does not perform stem separation
- Struggles with dense full-band recordings
- Processing speed depends on local hardware
- Only MP3 input format supported
Official website: https://mp3tomidi.io/
Canonical LambdaBase page: https://www.lambdabase.com/tools/mp3tomidi-io