Music Theory Reference – Chords, Scales & Intervals
Intervals
Technical name per semitone distance
Interval
Technical name
1 semitone
minor second
2 semitones
major second
3 semitones
minor third
4 semitones
major third
5 semitones
perfect fourth
6 semitones
tritone
Interval
Technical name
7 semitones
perfect fifth
8 semitones
minor sixth
9 semitones
major sixth
10 semitones
minor seventh
11 semitones
major seventh
12 semitones
octave
Basic Chords
Common triads & suspended chords
major triads
minor triads
diminished triads
augmented triads
suspended second chords
suspended fourth chords
Scales
Most-used scale families
major scales
natural minor scales
harmonic minor scales
melodic minor scales
major pentatonic scales
minor pentatonic scales
blues scales
chromatic scales
Seventh Chords
Common seventh chord families
dominant seventh chords
major seventh chords
minor seventh chords
minor major seventh chords
diminished seventh chords
augmented seventh chords
half-diminished seventh chords
augmented major seventh chords
Other Chords
Additional chord types
diminished triads
augmented triads
augmented chords
The names of piano keys
Note that the interval between two adjacent sounds in this table is one semitone horizontally and one octave vertically.
with frequencies:
What you can do on this page
This is a reference page rather than a lesson: the interval table, the chord and scale
families, and a playable map of every key with its frequency. Click any key in the map to
hear it — the notes are laid out exactly as they sit on the keyboard, one semitone apart
horizontally and one octave apart vertically.
Use it as a lookup while you learn. If a song page mentions a major third, the interval
table tells you it is four semitones. If you are working on the C major scale, the scale
list shows you which family it belongs to and where to go next.
How chords, scales and intervals fit together
A scale is a set of notes, a chord is a few notes from that set played together, and an
interval is the distance between any two of them. That is the whole hierarchy: learn the
twelve intervals and you can build any scale; learn a scale and you can build every chord
that belongs to it.
In C major the practical version is short. The scale is C D E F G A B, the three most
useful chords are C, F and G, and the shape that builds each of them is a major third
stacked on top of a minor third. Everything else on this page is a variation on that idea.
Using the keyboard map below
The two grids at the bottom of the page show the same keyboard twice: once with note names,
once with frequencies in hertz. Each row is one octave, and the rows step down from octave
6 to octave 1.
Middle C is the C in the octave 4 row, and it is the reference point every other note is
measured from. Press it, then press the same C one row up, and you hear an octave: twelve
semitones, the same note name, twice the frequency.
Keep learning
Piano chords chart — all 12 major and minor triads, seventh chords and inversions
Piano scales — the major scale formula, all 12 major scales, minor and pentatonic scales
Piano notes — note names, octaves and the full keyboard map
Piano intervals — every distance named, with the songs that train your ear