Online Keyboard Synth

Online Keyboard Synth is a free keyboard synthesizer that runs entirely in the browser. Open the page and start playing — there is nothing to install, no account to create and no plugin to load.

It is built for the moments when you want to play immediately: trying out a melody you have just thought of, showing a student a scale, or filling five spare minutes with something musical.

Notes can be triggered with the computer keyboard, the mouse or a touchscreen, and external MIDI controllers are supported for those with hardware. Sounds are shaped with selectable waveforms and presets, plus built-in reverb and delay. Octave controls extend the playable range, and chords can be played rather than single notes. A built-in recorder captures performances for playback.

The synthesizer runs on desktop, tablet and mobile browsers and is free and ad-free. It suits beginners getting a feel for keys before buying an instrument, music teachers running a quick demonstration or showing intervals, songwriters sketching a melody before opening a full DAW, and anyone who wants to play a few notes during a break.