Keys and intervals
Key signatures and sound
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You can always create as many flashcards as you like, free of charge.
If you would rather use a ready-made deck such as Keys and intervals, we ask you for a small sum in return. For €1.29 once you get 92 flashcards, sorted into 4 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.
- Cards
- 92
- Categories
- 4
- Price
- €1.29
Free, no account, no ads
What is in this deck
With this deck you learn 46 basics of music theory: key signatures of major and minor keys, relative keys and the intervals, asked both ways.
How many accidentals does A♭ major have, which key is relative to C major, and how many semitones is a major sixth?
22 keys with their accidentals, 13 intervals with their semitones, plus the relative keys. All asked both ways round.
Note names appear as each language writes them: B♭ major is B-Dur in German, si bémol majeur in French, 変ロ長調 in Japanese. German H is B elsewhere, and that trap is in the deck.
The categories decide what comes up: start with “Intervals” alone and add the rest when you are ready.
What you learn
- Accidentals of every major and minor key
- Semitones from unison to octave
- Relative keys and their accidentals
The categories
4 categories sort the 92 cards. You can filter by category and take on what is due right now.
- Intervals
- Major keys
- Minor keys
- Relative keys
What you get
Here are three of the 92 cards you get when you buy the deck.
Question
How many accidentals does C major have?
Answer
no accidentals
Note
C major sits at the centre of the circle of fifths: the sharp keys grow to the right, the flat keys to the left. Mozart's Sonata K. 545 is in C major.
Question
Which key has no accidentals (major)?
Answer
C major
Note
C major sits at the centre of the circle of fifths: the sharp keys grow to the right, the flat keys to the left. Mozart's Sonata K. 545 is in C major.
Question
With how many accidentals is A minor written?
Answer
no accidentals
Note
The harmonic minor scale needs the leading note G sharp; it appears as an accidental in the bar, not in the key signature. Grieg's Piano Concerto op. 16 is in A minor.
Learning with Qardbox
You see a card, you think, you turn it over and say whether you knew it. A round asks nothing more of you, and how the app works out the next date from that is on the page about FSRS-6.
What sits comes back less often, what wobbles comes back soon. You set a daily goal, and when nothing is due the app tells you exactly that instead of inventing work for you. How a round goes is shown on the learning page.
Everything stays on your device. No account, no sign-up, no ads. After the purchase the deck sits in your library like any other subject and can be studied, reordered and extended just like your own.
What it costs, and what it doesn’t
Qardbox itself costs nothing, and it stays that way. Every function is there from the start, with no subscription, no ads and no tiers; what that rests on is on the page about what it costs.
Your own cards stay unlimited, and decks from friends or from the family you read in without a limit, from a file as well. You do not need this deck in order to learn with Qardbox.
It is a shortcut: 92 checked cards for €1.29, once, with Family Sharing. The work you would otherwise do is already done. The App Store shows the price in your currency.
Common questions
Do I have to pay for Qardbox?
No. The app is free, with no subscription and no ads, and every feature is included. The only thing that costs money is a ready-made deck like this one, €1.29 once.
Could I make these cards myself?
Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.
How many cards are in Keys and intervals?
92 cards, sorted into 4 categories.
Do I need a connection to study?
Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.
Which devices does this run on?
On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.
Is there a Qardbox for Android?
No. Qardbox is there for iPhone, iPad and Apple Watch, not for Android and not in a browser.
Other decks that go with this one
Get started
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