Top 3 HTML Synthesizer Projects

webaudiofont

2 863 5.0 HTML

Use full GM set of musical instruments to play MIDI and single sounds or effects. Support for reverberation and equaliser. No plugins, no Flash. Pure HTML5 implementation compatible with desktop and mobile browser. See live examples.
teensy-eurorack

5 217 5.3 HTML

Hardware Design: Eurorack shield for teensy 4.1 with 14 in / 16 out analog channels
WorkOS

workos.com sponsored

The modern identity platform for B2B SaaS. The APIs are flexible and easy-to-use, supporting authentication, user identity, and complex enterprise features like SSO and SCIM provisioning.
synth-diy

1 72 7.3 HTML

Mostly Eurorack projects

NOTE: The open source projects on this list are ordered by number of github stars. The number of mentions indicates repo mentiontions in the last 12 Months or since we started tracking (Dec 2020).