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Secondary Dominant Chords: Borrowing a V for Any Chord
Secondary dominant chords are dominant chords aimed at a chord other than the tonic. In C major, D7 is the V of G, so it is written V/V. It sounds like a short visit to the key of G, and it makes the arrival on G much stronger.
No account, no download. The demo has limited content. Advanced features are in ChordRunner Premium.
- MIDI keyboard
- Digital or acoustic piano
- Guitar
- Computer, phone or tablet
Find one in two steps
- Pick the target chord, for example Dm (ii in C).
- Go a 5th above its root and build a major chord or a dominant 7th: A, or A7. That is V/ii.
All of them in C major
- V/ii: A7, going to Dm.
- V/iii: B7, going to Em.
- V/IV: C7, going to F.
- V/V: D7, going to G.
- V/vi: E7, going to Am.
- There is no V/vii°: a diminished chord cannot act as a temporary tonic.
Secondary Dominant Chords: Borrowing a V for Any Chord
ChordRunner is a browser game that teaches piano and guitar chords: a chord appears on screen, you play it on a real instrument, and your runner jumps.
Play the demoHow to spot one in a song chart
Look for a major or dominant 7th chord that does not belong to the key, followed by a chord a 5th lower. E7 to Am in C, or A7 to Dm. The note that is outside the key, G# in E7 or C# in A7, is a temporary leading tone and rises to the next root.
Put it under your fingers
Type a progression like C A7 Dm G7 C into ChordRunner and it loops while you play it on a MIDI keyboard, or a piano or guitar through the microphone (advanced feature in ChordRunner Premium). After a few rounds you will hear the pull of each secondary dominant before you see the chord name.
The levels in ChordRunner
- Beginner: major, minor, augmented and diminished chords.
- Intermediate: adds sus2 and sus4.
- Advanced: adds 6th, 7th and 9th chords.
- Pro: adds 11th, 13th and altered chords; an adaptive mode adds the next family when you are ready.
Common questions
What is a secondary dominant chord?
A dominant chord, usually a dominant 7th, that resolves to a chord of the key other than the tonic. D7 to G in C major is V/V.
How do you write a secondary dominant?
With a slash between two Roman numerals: V/V, V7/ii, V/vi. The part after the slash is the target chord.
Do secondary dominants work in minor keys?
Yes. In A minor, A7 is V/iv, going to Dm, and B7 is V/V, going to E. The idea is the same: a dominant a 5th above the target.
Which instruments work?
A USB MIDI keyboard, detected automatically, or a piano or guitar through the microphone. Everything runs in Chrome or Edge on a computer, tablet or phone.
How is this different from apps where you tap the screen?
Tapping trains your eyes and fingers on glass. Here you press real keys or fret real strings, and the game hears the actual notes, so what you practise is exactly what you will play on your instrument.
Is everything in the demo?
The demo has limited content. Advanced features are in ChordRunner Premium.
Your instrument is the controller.
ChordRunner is a browser game that teaches piano and guitar chords: a chord appears on screen, you play it on a real instrument, and your runner jumps. MIDI keyboard or microphone, both work.
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