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First Inversion Chords: Why a Small 6 Means the 3rd Is in the Bass
A triad is in first inversion when its 3rd is the lowest note. C major with E at the bottom, E G C, is the classic example. Figured bass writes it as 6/3, shortened to a single 6, so I6 means the tonic chord with its 3rd in the bass.
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
Read it from the bass up
Take E G C. From E, G is a 3rd up and C is a 6th up: that is 6/3. The 3 is always there in a triad, so books keep only the 6. In C major the first inversions are I6 (E G C), ii6 (F A D), IV6 (A C F) and V6 (B D G).
What first inversion sounds like
Lighter than root position, a bit in motion. The bass is no longer the name of the chord, so the ear waits for the next step. That is why first inversion chords sit in the middle of phrases and almost never at the very end.
First Inversion Chords: Why a Small 6 Means the 3rd Is in the Bass
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 demoThree places you will meet it
- A walking bass: C to E to F (I, I6, IV) climbs by step instead of jumping.
- Before the dominant: ii6 to V is one of the most common moves in tonal music, because the bass F steps to G.
- V6 to I: B in the bass rises to C, the leading tone resolving right where you hear it.
Train the shape, not only the name
On the keys, first inversion has the gap at the top: E and G close together, then a jump to C. ChordRunner counts it as the right chord, and the practice keyboard can show any chord in root position, first or second inversion, so you see the shape before you play it.
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 does a 6 mean next to a chord?
In figured bass and Roman numeral analysis it means first inversion: a 6th and a 3rd above the bass, so the chord’s 3rd is the lowest note. I6 in C is E G C.
How do I write a first inversion chord?
Write the Roman numeral of the chord and a small 6 at its top right: I6, ii6, V6. In pop symbols the same chord is a slash chord, like C/E.
Is a first inversion chord the same as a 6th chord?
No. A first inversion keeps three notes (E G C). A pop C6 adds a fourth note, A (C E G A). Only the context tells you which one a 6 means.
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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