Structured MIDI data
MIDI to JSON
Export a MIDI file as a versioned JSON object with header data, tracks, notes, tempo points, duration, and a key estimate for scripts or AI workflows.
Open a MIDI file
Stay on-device. Start empty if you have no file, or try a public demo.
Off-grid notes, wild velocities, leftover gaps — the dirty AI-song export producers actually get.
A clean four-bar piano phrase you can transpose, quantize, or reshape immediately.
Drums, bass, and chords on separate tracks for mute, solo, and merge practice.
The same hook after quantize and velocity cleanup — the after shot for the messy export.
Your file stays on this device unless you explicitly use Creator Cloud. After an edit, one local recovery copy is saved in this browser until you replace or clear it.
Creator Cloud
Keep the versions and extend the phrase.
Creator Cloud adds cloud history and reviewed AI MIDI edits a month. The tool you are using stays free.
- 60 reviewed AI MIDI edits each month
- 50 cloud projects with 100 versions each
- Cancel anytime; the free editor stays free
A predictable shape for code
The export starts with a schema name, editmidi.midi.v1, so a script can check what it received. Header fields describe the SMF type, PPQ, and track count. Duration records seconds, bars, and time signature. Tempo is an array of tick and microseconds-per-beat points.
Each track includes its name, one-based channel, program number, note count, and an array of notes. Every note has a number, name, channel, start and end ticks, duration, and velocity. A detected key object is included when the file has pitched notes.
Useful for AI and analysis workflows
A language model cannot open a binary .mid file directly. A JSON export gives it a bounded, readable representation of the notes and structure that you can paste into a prompt, store as a fixture, or validate with a schema.
Keep the original MIDI as the source of truth. JSON is a derived view: it does not preserve every controller, SysEx message, or device-specific detail. If a downstream tool needs to reconstruct the file exactly, keep the .mid as well.
Schema and copy workflow
Use Download JSON when you need a file, or Copy when you are pasting into a notebook or chat. The preview shows the beginning of the document; the download and copy actions use the complete object, not the shortened preview.
The object is generated from the current document in the browser. If you edit the MIDI and export again, the new JSON reflects the new note positions. Nothing is uploaded and no account is required.
Size and privacy boundaries
A file with thousands of notes can produce a large JSON document. The preview is intentionally truncated, and the browser may take a moment to serialize a large file. The export is limited by the same 20,000-event editor boundary as every other tool.
The JSON includes note and tempo data, not audio. It does not contain your account identity, filename history, or cloud project metadata. Treat it like the MIDI itself: it may still contain musical ideas you do not want to share publicly.
Keep the same fileAll EditMIDI tools
Open the full index
Every page runs on the same browser MIDI engine, so you can move between them without uploading or re-importing your file.
- MIDI editor online — edit notes, tracks, and velocity in the browser
- MIDI player online — preview tracks, scrub, and loop without uploading
- Transpose MIDI online — change key without losing tempo or controllers
- Change MIDI BPM online — replace a tempo map with one steady value
- Quantize MIDI online — snap note starts and ends to a musical grid
- MIDI velocity editor — set note dynamics from 1 to 127
- MP3 to MIDI converter — turn a melody into an editable piano roll
- Audio to MIDI — sketch one melody from a local recording
- Suno MIDI cleanup — quantize and fix messy AI exports
- MIDI to MP3 — render a MIDI file to WAV or MP3 in this browser
- Piano roll viewer — see every note, pitch, and length in a .mid file
- WAV to MIDI converter — draft notes from an uncompressed recording
- Vocal to MIDI — turn a hummed or sung line into editable notes
- MIDI key finder — estimate the key, relative key, and Camelot code
- Merge MIDI files — combine two .mid files into one multi-track project
- MIDI file checker — inspect structure, channels, tempo, and compatibility risks
- MIDI duration calculator — read seconds, bars, beats, and tempo points
- MIDI to CSV — export one row per note for a spreadsheet
- MIDI to video — record a vertical, square, or widescreen piano-roll clip
- MIDI cover art generator — export a 1500px PNG from the note pattern
- Humanize MIDI — add bounded timing and velocity variation with a repeatable seed
- MIDI velocity curve — reshape dynamics with a gamma curve
- MIDI note length editor — make notes shorter, legato, or staccato
- MIDI to WAV — render uncompressed 44.1 or 48 kHz audio locally