MIDI keyboards

A MIDI keyboard is a piano keyboard that sends your computer a message for every key you press: which key, how hard, and when. It makes no sound of its own. Chordzy listens to those messages, plays the notes, and grades what you played against the music on screen. That is the whole reason it wants one. The on-screen keys work without it, but your hands learn very little from a mouse.

Shops call the same thing a MIDI controller, a MIDI keyboard controller, or a USB MIDI keyboard. A digital piano with a USB port counts too. This page covers what to buy, how to plug it in, and why a browser sometimes refuses to see it.

A full-size piano has 88 keys. Many MIDI keyboards have fewer, and every key you do not have is a piece of music you cannot play as written. 61 keys covers most beginner pieces. 25 does not.

The other thing to check is how the keys feel. Keyboards sold as "hammer-weighted", "fully weighted" or something similar are harder to press, because they copy the mechanism inside an acoustic piano. That is a feature, and it is worth starting on. Playing weighted keys builds the gentle strength your hands need to play fluidly and with real dynamics. A light plastic key never asks for it.

The best keyboard for learning piano is 88 weighted keys with a USB port. Everything after that is budget. If you are buying one for Chordzy, four things matter, in this order.

1. Keys. 88 if you have the room and the budget, 61 if you do not. Weighted if you can, for the reasons above.
2. A USB port for a computer. Almost every keyboard sold today has one. On the back panel it is labeled USB to Host, USB Computer or "USB MIDI". A keyboard with only the old five-pin MIDI socket needs a separate USB MIDI interface.
3. Velocity. Nearly all keyboards send how hard you pressed, and Chordzy uses that for dynamics. A toy keyboard may not.
4. A pedal socket. Not needed on day one. Wanted by month three.

You do not need weighted keys to start learning. Any keyboard that sends velocity will teach you to read music and find the notes, and plenty of players spend a first year on one. What an unweighted keyboard costs you is control: light keys feel the same whether you lean on them or brush them, so your fingers get no feedback about how loud a note came out, and the first hour on a real piano feels like pushing through sand. If the choice is 88 unweighted keys or 61 weighted ones at the same price, take the weighted ones.

Bluetooth MIDI keyboards work too, but the pairing happens in your operating system before any browser can see them. USB skips all of that. When in doubt, buy the cable.

Plug the keyboard into the computer with a USB cable and switch it on before you open Chordzy. Press Connect MIDI keyboard and say yes when the browser asks. When it works, that is the entire process. The rest of this page is for when it does not.

Two things trip people up more than everything else combined.

The port. Many keyboards have two USB sockets. The one that talks to a computer is usually marked USB to Host or USB Computer. The other, USB to Device, is for memory sticks, and no browser will ever see it.

The cable. A lot of cheap USB cables carry power and nothing else; there are no data wires inside. They look identical to the good ones. If the keyboard lights up but nothing appears on screen, swap the cable before you touch anything else.

If Chordzy still says it cannot see your keyboard, find your browser below.

Chordzy runs in every modern browser. The lessons, the sheet music and the on-screen keys are the same everywhere. Reading a real keyboard is a separate question, and the answer depends on one browser feature: Web MIDI.

Your device is almost never the problem. iPhones and iPads have talked to MIDI hardware for years through Core MIDI, and plenty of native apps use it. What some browsers lack is the API that hands it to a web page.

Safari has never shipped Web MIDI, on a Mac or on an iPhone. Apple's stated reason is fingerprinting: a MIDI device reports identifiers that could be used to recognize you again. That is true, and the result is that your piano cannot talk to your browser. There is no setting and no feature flag. Nothing on your end can fix it.

On an iPhone or iPad the same goes for Chrome, Edge and Firefox. Apple requires every browser there to run on Safari's engine, so they inherit the gap along with it, whatever the icon says.

Real keys on an iPhone or iPad

There is one way, and it is not Safari. Web MIDI Browser (on the App Store, by Takashi Mizuhiki) is a browser built for exactly this gap. It implements Web MIDI itself on top of iOS's own MIDI stack, Bluetooth MIDI included. Open Chordzy inside it and a connected keyboard just works.

It is a third-party app we do not control, so call it a workaround rather than a recommendation. It is also the only way to use a hardware keyboard with the website on iOS.

The short version

• On a computer: Chrome, Edge, Opera or Firefox. On a Mac, Safari is the one browser that will not do this. The others all will.
• On Android: Chrome, Edge or Opera. Firefox for Android has not shipped Web MIDI.
• On an iPhone or iPad: the on-screen keys work in any browser. For a real keyboard, use Web MIDI Browser.

The day Apple ships Web MIDI, this page changes.

The first time you press Connect MIDI keyboard, the browser asks whether Chordzy may use your MIDI devices. Dismiss that prompt, or press Block, and the browser remembers. From then on it refuses silently. Your keyboard can be plugged in, switched on and working perfectly, and Chordzy sees nothing.

The tell is the line under the button. If it says MIDI access is blocked, this is your problem, and nothing you do to the keyboard will change it.

Chrome, Edge, Opera and Brave on a computer

1. Click the icon at the left of the address bar. Depending on your version it is a sliders icon or a padlock.
2. Choose Site settings.
3. Find MIDI devices and set it to Allow.
4. Reload the page and press Connect MIDI keyboard again.

Or paste chrome://settings/content/midiDevices into the address bar to go straight there, and remove chordzy.com from the "Not allowed" list.

Chrome on Android

1. Tap the ⋮ menu, then the ⓘ icon beside the address.
2. Tap Permissions, then MIDI devices, then Allow.
3. Reload and try again.

A phone also needs a USB OTG adapter between it and the keyboard's cable. Some phones cannot power a keyboard that has no supply of its own. If the keyboard's lights stay off, that is what happened.

Firefox on a computer, version 108 and later

1. Click the padlock in the address bar.
2. Under Permissions, find MIDI and clear the blocked setting.
3. Reload the page and try again.

Firefox asks again every session unless you tick Remember this decision.

Safari, and any browser on an iPhone or iPad

There is no permission to grant. Safari has no Web MIDI at all, and every browser on iOS runs on Safari's engine. A hardware keyboard on an iPhone or iPad goes through the Web MIDI Browser app; see which browsers can see a keyboard.

MIDI is allowed and it still cannot see the keyboard

• Close any other program that uses the keyboard. On Windows especially, a DAW or a synth app can hold the MIDI port open, and then nothing else can read it, your browser included.
• Unplug the keyboard, reload the page, then plug it back in.
• Try the keyboard's other USB port, and a different cable (see plugging it in).
• Restart the browser. A keyboard plugged in after the browser had already refused permission sometimes needs a fresh start before it appears.