Online MIDI Player, Editor and MIDI to MP3 Converter
Play, edit and convert MIDI entirely in your browser.
100% local processing, no file uploads. Fast, private, and free.
No upload • Privacy‑friendly • Works offline (PWA ready)
from 99+ happy users
Built with modern Web Audio stack
What is MIDI Toolbox
MIDI Toolbox is an online suite for MIDI creators: a fast MIDI Player, a powerful in-browser MIDI Editor, and a MIDI → MP3/WAV converter. Everything runs locally in your browser for privacy.
- Online MIDI PlayerLoad and preview MIDI instantly with precise timeline and looping.
- MIDI Editor (in-browser)Edit piano roll, quantize, adjust velocity and export. No install.
- MIDI to MP3/WAVExport high-quality audio with configurable bit rate and normalization.
Why choose MIDI Toolbox
Fast, private and reliable MIDI tools that work anywhere.
Get started in 3 steps
Start with the Player, edit in the Editor, and export with the Converter.
Key Features
Everything you need for MIDI playback, editing and exporting.
Precise Timeline & Loop
Scrub, set A/B loop points, and practice efficiently.
Piano Roll Editing
Add, move, lengthen notes with snapping and quantize.
Velocity & CC Basics
Adjust velocity and essential MIDI controls quickly.
Instrument Presets
Switch GM instruments and save track settings.
High-quality Export
MP3/WAV export with bitrate, sample rate and fade.
Privacy by Design
Local processing by WebAudio & Tone.js, no uploads.
Loved by musicians and students
Fast workflow • Clear UI • Reliable exports
Local Processing
100%
No uploads
Tools
3+
Player/Editor/Converter
Formats
2
MIDI / MP3
What users say
Creators use MIDI Toolbox to sketch ideas and export tracks quickly.
Indie Producer
Music Creator
Playback, quick edits and MP3 export all in one place. The A/B loop is perfect for practice.
Music Student
Learner
I can slow down, loop difficult bars and tweak notes—right in the browser, no install needed.
Piano Teacher
Educator
My students love the visualizer. It helps them understand note duration and rhythm without getting overwhelmed by sheet music.
Game Dev
Developer
The MIDI to JSON converter is a lifesaver for my web games. Fast, accurate, and runs offline.
Frequently Asked Questions
Have another question? Email us any time.
Will my files be uploaded?
No. All playback, editing and conversion run locally in your browser for privacy.
How to export MP3/WAV?
Open Converter, drop your MIDI, choose bitrate/sample rate/normalization and export.
Can I edit MIDI online?
Yes. The in-browser MIDI Editor supports piano roll, quantize and velocity adjustments.
Which browsers are supported?
Latest Chrome/Edge/Firefox/Safari. Mobile is partially supported for playback.
Is it free?
Yes. Core tools are free to use. Advanced features may be added later.
Can I open it in the Player/Editor?
Yes. Tools are linked. You can send files between Player, Editor and Converter.
Create, edit and export MIDI in your browser
Open a tool and start now—no install required.
WebMIDI Tools: Online MIDI Player, Editor, Converter
MIDI tools in the browser let you play, edit, convert and generate MIDI with zero installs. Our MIDI tools handle tempo, key and channel cleanup, so creators can analyze files, fix issues and export clean results quickly. With WebMIDI support, these MIDI tools keep audio workflows fast, accurate and privacy‑friendly. Use the MIDI tools to practice, arrange and share ideas across DAWs and devices.