Questions
The ones worth answering before you spend any time in the app.
What does it cost?
Nothing, for everything the app does today. No account, no card, no trial period. If accounts and sync ever get built they’ll need a server, and that part might cost something. Pricing has the details.
Do I need an account?
No. There isn’t one to make. You open the page and start playing.
Where are my chords and sheets stored?
In your browser, in local storage. Nothing is uploaded to a server, and that cuts both ways: it also means nothing is backed up.
If you clear your browsing data, use private browsing, or switch to another browser or device, your sheets won’t be there. Export anything you’d be upset to lose. Back up everything writes every sheet and your whole chord library to one .keyriff.json file, and opening that file again puts it all back. A single sheet can be exported the same way when you only want to hand one to somebody. A PDF is for printing rather than for opening again.
It’s a file you have to remember to make, though, and it’s only as recent as the last time you made one. Automatic backup, and syncing between your phone and your desktop, would need an account, which is the main reason one might eventually exist.
Does it work on a phone?
Yes, and it’s the same app rather than a reduced one. The keyboard scrolls sideways, saved chords sit in a tray at the top of the sheet instead of a side panel, and the controls are sized for fingers. Long-press a chord card to drag it.
Which browsers work?
Recent Chrome, Firefox, Safari and Edge, on desktop and mobile. Safari gets tested on a real WebKit engine rather than a phone emulator in Chrome, because that difference once hid a bug that left the piano completely dead in Safari for a whole release.
Can I plug in a MIDI keyboard?
Not yet. Input today is mouse, touch and the computer keyboard, which has an octave mapped to it: A to K, with the black keys on the row above. MIDI would be a sensible thing to add and it isn’t in the app.
Does it need to be online?
To load the page, yes. There is no offline mode, so opening Keyriff with no connection gets you nothing. After that, almost nothing needs the network. Chord detection is calculated in the page and works straight away, and your sheets are read from your own browser. The sampled piano is about a megabyte of audio that downloads in the background, and if it hasn’t arrived, or the connection drops, the keyboard still works and still names chords. It goes silent, not dead.
How many notes does it need to name a chord?
Three. Two notes is an interval, and there isn’t enough information in one to name a chord confidently. When several names fit, the alternatives are shown next to the main one.
How does it know which chord comes next?
It goes by the key your sheet is in. The “Goes well next” row offers the chords that commonly follow the one you’re holding, each labelled with the numeral it plays, and tapping one puts it under your hands. When the chord you’re holding sits outside the key it suggests nothing rather than inventing something. There’s no model behind this and nothing leaves your browser: it’s ordinary harmony, worked out in the page.
Can I print a sheet?
Yes. Export produces a PDF with a small keyboard diagram for every chord, laid out by section. It prints readably in black and white.
Who makes this?
One person, in their own time. It isn’t a company, and there isn’t a team behind the word “we”.