How to play a MIDI keyboard in your browser, with no software

You do not need a DAW, a driver or a piano app to play a MIDI keyboard. Modern browsers can read MIDI directly, through a standard called Web MIDI, so an online piano can hear every key you press — how hard you press it, and the sustain pedal too.

Connect in four steps

1. Plug the keyboard in with a USB cable, and switch it on if it has its own power.
2. Open the online piano in Chrome, Edge, Opera or Firefox.
3. Press Connect MIDI. The browser asks whether the page may use your MIDI devices. Choose Allow. Firefox shows its own permission prompt the first time.
4. Play. Keys light up on screen as you press them. How hard you strike is passed through, and so is a sustain pedal plugged into the keyboard.

The harmonium works the same way, with sargam labels on every key.

Which devices work

Device	Works?
Windows, Chrome or Edge	Yes
Windows, Firefox	Yes, after its permission prompt
Mac, Chrome or Firefox	Yes
Mac, Safari	No — Safari has no Web MIDI
Chromebook	Yes
Android, Chrome	Yes, with a USB-C or USB OTG adapter
iPhone and iPad, any browser	No

The iPhone limit is not a setting. Apple requires every browser on iOS to use Safari’s engine, and that engine does not support Web MIDI. On an iPad, a dedicated piano app is the way to use a MIDI keyboard.

Does my keyboard send MIDI?

Almost every digital piano and controller keyboard made in the last fifteen years does, over USB. Look for a square USB-B or a USB-C port labelled “USB to Host” or “USB MIDI”. Plug that into the computer.

A keyboard with only round 5-pin MIDI OUT sockets also works through a USB–MIDI interface cable. Connect the cable’s IN plug to the keyboard’s MIDI OUT.

A USB socket labelled “USB to Device” or a flash-drive symbol is for memory sticks, not for the computer.

When nothing plays

Work down this list. Most problems end at the first or second step.

• Did you allow access? If you dismissed the prompt, click the icon at the left of the address bar, set MIDI devices to Allow, and reload.
• Is another program using it? On Windows, many keyboards can only talk to one program at a time. Close any DAW, notation program or keyboard utility, then reload.
• Replug and reload. Unplug the USB cable, plug it back in, then reload the page. Browsers read the device list when the page connects.
• Try another cable or port. Some USB cables carry power only. A cable that charges a phone may not carry data.
• Check the keyboard’s own settings. Some keyboards have a “Local” or “MIDI out” option. It should be on.

Sound is late or crackles

• Use wired output. Bluetooth headphones and speakers add a delay you can feel under your fingers. Wired headphones, or the computer’s own speakers, respond much faster.
• Close heavy tabs. Video calls and games compete for the same processor.
• Plug the laptop in. Some laptops slow down on battery to save power.

Recording what you play

Press Record, play, press Stop, and download an MP3 to share or a MIDI file to open in music software. The recording is rebuilt from the notes you played, not captured through a microphone, so it is clean even in a noisy room.