MIDI Notes Player – Play any MIDI note sequence in the browser

Name: MIDI Notes Player – Play any MIDI note sequence in the browser
Availability: InStock
Author: mayerwin

by mayerwin·Mar 19, 2026·1 point·0 comments

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AI Analysis

●MidCozyNiche Gem

Solfège parsing with French accidentals is unique, but browser MIDI players already exist.

Strengths

•Solfège input with French accidentals like ré and solb supports music theory workflows
•SoundFont playback with 50+ General MIDI instruments works offline in browser
•Any separator parsing handles messy clipboard data without preprocessing

Weaknesses

•No MIDI file import or export limits practical music production use
•Single-page utility with no persistence or project management features

Post Description

I one-shotted this app with Claude Opus 4.6 (Claude Code in VS Code), from idea to deployed GitHub Pages site in a single prompt.

Live demo: https://mayerwin.github.io/MIDI-Notes-Player/

It's a simple tool: paste a sequence of MIDI note numbers (like 60, 64, 67, 72) or note names (C4 E4 G4 C5) and hit Play. It also supports solfège (do ré mi fa sol), accidentals (Eb5, sol#4), any separator you want, and 50+ General MIDI instruments via SoundFont samples.

Für Elise is pre-loaded so you can try it immediately.

What Claude generated in one shot: - Vite + vanilla JS app (no framework) - Note parser supporting MIDI numbers, scientific pitch notation, and solfège (with French accidentals like solb, sold) - SoundFont-based audio playback with 50+ instruments - Real-time note validation with visual token display - Tempo/duration controls, keyboard shortcuts, animated playback - GitHub Actions CI/CD for automatic deployment - README, LICENSE, the whole thing

The only manual steps were creating the GitHub repo via gh CLI (which Claude also did through the terminal) and authorizing the push.

Stack: Vite, vanilla JS/HTML/CSS, soundfont-player, Web Audio API.

Source: https://github.com/mayerwin/MIDI-Notes-Player