About Keyboard Play
Our mission
Keyboard Play exists to make playing a musical instrument instant and universal — open a page and just play. No install, no sign-up, no instrument required.
How it works
Sound is synthesized in real time in your browser with the Web Audio API and SpessaSynth, a SoundFont2 engine running on a dedicated AudioWorklet audio thread. Seven sampled instruments — piano, Rhodes, organ, music box, synth, harp and marimba — come from the FluidR3 General MIDI soundfont. Recordings are encoded to MP3 with lamejs.
Why the instruments sound real
Many online instruments fake their sound with a single synthesized waveform — one shape of wave dressed up to suggest an instrument. Keyboard Play does the opposite. Each of the seven instruments is a real recorded sample drawn from a SoundFont: the actual tone of a real piano, marimba or harp, complete with the way each note blooms at the attack and fades as it decays. That is why a chord on the music box tinkles and vanishes while the same chord on the organ holds steady — they are genuinely different instruments, not one sound with the tone knob turned. Learn more in our guide to the seven instrument sounds.
Why it feels responsive
The synthesis runs on a dedicated AudioWorklet audio thread, separate from the thread that draws the page. So even when the browser is busy with animation or layout, the audio keeps running on time — notes respond with low latency whether you click, tap, type or, in supporting browsers such as Chrome and Edge, play a connected MIDI keyboard with real velocity.
Why your recordings stay private
When you record, the audio is encoded to MP3 by lamejs entirely inside your browser. The audio data never leaves your device — nothing you play is uploaded to any server. Whatever you record belongs to you. See the privacy policy for the full details.
How Keyboard Play compares
There are many ways to play an instrument online. Here is how Keyboard Play compares to the common alternatives:
| Alternative | Common drawback | Keyboard Play |
|---|---|---|
| Older online piano sites | Dated interfaces; thin, synthetic tone from a single waveform | Modern interface; seven real sampled instruments |
| Free piano apps | Ad-heavy, clunky touch, often need install | No install, no sign-up, plays in the browser |
| Old Flash-based tools | No longer work, especially on mobile | Pure Web Audio + AudioWorklet, works on modern browsers |
| Downloadable piano software | Installers, updates, disk space | Open a URL and play |
| Generic online keyboards | One fake piano sound with no character | Seven distinct real instruments for different moods |
Who makes Keyboard Play
Keyboard Play is built by a small team of musicians and web audio developers who want real, expressive instruments to be reachable to everyone. Because synthesis runs entirely in the browser on a dedicated audio thread, notes respond with low latency whether you click, tap or type. We keep refining the instrument list, the three keyboard layouts and the MP3 recording pipeline, and we welcome feedback through our contact page.
Explore
- Play the online piano
- Try the other instruments
- Learn piano chords
- Explore scales
- Why our instruments sound real
- Read the blog
Have feedback? Get in touch.