B7 piano chord, B dominant 7th notes and fingering.

The B7 piano chord is B dominant 7th: B, D#, F# and A. It is the B major triad (B, D#, F#) with a minor seventh (A) added on top, ten semitones above the root. A plain 7 in a chord name, as in B7, always means this flat seventh, not the major seventh.

How to play B7 on piano

1. Find B on the keyboard. B is the white key just right of the group of three black keys, the last white key before C.
2. With your right hand, put finger 1 on B, finger 2 on D#, finger 3 on F# and finger 5 on A. Finger 1 is the thumb.
3. Press all four keys together. In root position they run from B3 to A4, a reach of 10 semitones. Play chord sounds them together and Arpeggio sounds them one by one, from the bottom up.
4. Click Left hand to see the left hand. It plays B2 to A3, one octave lower: B with finger 5, D# with finger 3, F# with finger 2, A with finger 1.
5. The cards under the keyboard hold the four positions, with B, D#, F# and A at the bottom in turn. Play and Arpeggio on a card play that position.
6. Open Note names. As written the keys read B, D#, F# and A. Sharps shows B, D#, F# and A, and Flats shows B, Eb, Gb and A. This chord is written with sharps, so As written and Sharps match.

How B7 is built

Counted from the root, the formula is 0, 4, 7, 10. Stacked on each other the gaps are 4 + 3 + 3: a major third, a minor third and another minor third. The third (D#) and the seventh (A) are 6 semitones apart, which is a tritone, the most tense interval in the chord. That pair is what makes the chord lean toward a resolution.

Worked example: the pitch of B3. On a piano tuned to A4 = 440 Hz, a note 10 semitones below A4 has the frequency 440 × 2^(-10/12), which is about 246.94 Hz. D#4 is 6 semitones below A4, so 440 × 2^(-6/12) gives about 311.13 Hz.

What the keys look like under your hand

B has a black key on its left (Bb) and none on its right, because B and C are only a semitone apart. Two of the four notes are black keys (D# and F#) and two are white keys (B and A). Finger 2 presses D#, a black key between D and E. The middle fingers are the longest, so they reach black keys most easily. Finger 3 presses F#, a black key between F and G. The middle fingers are the longest, so they reach black keys most easily.

B7 inversions and fingering

B7 has four positions. In root position B is at the bottom. In the first inversion, D# is at the bottom and the chord is written B7/D#. In the second inversion, F# is at the bottom and the chord is written B7/F#. In the third inversion, A is at the bottom and the chord is written B7/A. The tightest reach, 8 semitones from the lowest key to the highest, is the first inversion. The widest, at 10, is the root position.

The keys that hold B7

B7 fits two of the major and natural minor keys that have a standard key signature, which means every note of it comes from that key's scale. The simplest is E major, with 4 sharps, where it is chord V7.

Progressions that use B7, with the chord numbers and the chords in that key:

• E major: Imaj7-IVmaj7-V7-Imaj7, which is Emaj7, Amaj7, B7, Emaj7, the three-chord cadence of folk, rock and blues.
• C# minor: i7-VII7-VImaj7-VII7, which is C#m7, B7, Amaj7, B7, a rocking figure between VII and VI.
• E major: vi7-IVmaj7-Imaj7-V7, which is C#m7, Amaj7, Emaj7, B7, the four-chord loop started from the vi chord.

Blues: a 12-bar blues in B is built on B7, E7 and F#7.

Here is a worked example in E major. The chord before B7 in the first progression above is Amaj7 (A, C#, E and G#). From Amaj7 in root position, the closest way to reach B7 is its third inversion (A, B, D# and F#, lowest note first): one note stays where it is, and the others move 5 semitones in total, counting each note against the note in the same place from the bottom.

Look at the top three notes of B7: D#, F# and A make a D# diminished chord (D#, F# and A). A dominant 7th is a diminished triad with the root added underneath.

What B7 sounds like

The dominant 7th is restless. Its tritone between D# and A pulls toward a resolution, and the chord most naturally moves to E, a fifth below B. It is the sound of the blues too, where every chord can be a dominant 7th.

Here B7 is the V7 chord in E major and the VII7 chord in C# minor. In a 12-bar blues in B the three chords are B7, E7 and F#7. In minor keys the same chord appears as V7 of E minor, using the raised seventh of the harmonic minor scale.

A common mistake with B7

A common mistake is pressing A# instead of A on top, one semitone higher than the seventh of B7. That gives Bmaj7 (B, D#, F# and A#), which sounds soft where B7 sounds restless. Check the top note: it should be the lower of the two keys.

Chords to learn next

Chords close to B7: B major (the same chord without the seventh; shares B, D# and F#); Bmaj7 (a major seventh instead; shares B, D# and F#); Bm7 (a minor third instead; shares B, F# and A); E major (the chord it leads to; shares B).

Once B7 feels easy, play it and then E major to hear the chord resolve. For chords beyond these six types, and for guitar and ukulele shapes, use the chord finder. To play along with your computer keys, open the virtual piano. The piano chords page lists all 72 chords.