My Chord Finder
C
C frets from the sixth string to the first: x 3 2 0 1 0.
C spelling: C, E, G.
C sounding notes: C3 (1), E3 (3), G3 (5), C4 (1), E4 (3).
C open strings: third string, G (G3), first string, high E (E4).
open chords
These open chords are 6 open-position majors, 5 minors, and 6 dominant 7s. The measured E major G#3 is 41.5 cents sharp of equal temperament.
Open major chords
Open position here means at least one open string and no fingered fret above 3. Each row is the first shape the guitar finder returns under that rule.
D
D frets from the sixth string to the first: x x 0 2 3 2.
D spelling: D, F#, A.
D sounding notes: D3 (1), A3 (5), D4 (1), F#4 (3).
D open strings: fourth string, D (D3).
E
E frets from the sixth string to the first: 0 2 2 1 0 0.
E spelling: E, G#, B.
E sounding notes: E2 (1), B2 (5), E3 (1), G#3 (3), B3 (5), E4 (1).
E open strings: sixth string, low E (E2), second string, B (B3), first string, high E (E4).
F
F frets from the sixth string to the first: 1 0 3 2 1 1.
F spelling: F, A, C.
F sounding notes: F2 (1), A2 (3), F3 (1), A3 (3), C4 (5), F4 (1).
F open strings: fifth string, A (A2).
G
G frets from the sixth string to the first: 3 2 0 0 0 3.
G spelling: G, B, D.
G sounding notes: G2 (1), B2 (3), D3 (5), G3 (1), B3 (3), G4 (1).
G open strings: fourth string, D (D3), third string, G (G3), second string, B (B3).
A
A frets from the sixth string to the first: x 0 2 2 2 0.
A spelling: A, C#, E.
A sounding notes: A2 (1), E3 (5), A3 (1), C#4 (3), E4 (5).
A open strings: fifth string, A (A2), first string, high E (E4).
Open minor chords
Am
Am frets from the sixth string to the first: x 0 2 2 1 0.
Am spelling: A, C, E.
Am sounding notes: A2 (1), E3 (5), A3 (1), C4 (b3), E4 (5).
Am open strings: fifth string, A (A2), first string, high E (E4).
Em
Em frets from the sixth string to the first: 0 2 2 0 0 0.
Em spelling: E, G, B.
Em sounding notes: E2 (1), B2 (5), E3 (1), G3 (b3), B3 (5), E4 (1).
Em open strings: sixth string, low E (E2), third string, G (G3), second string, B (B3), first string, high E (E4).
Dm
Dm frets from the sixth string to the first: x x 0 2 3 1.
Dm spelling: D, F, A.
Dm sounding notes: D3 (1), A3 (5), D4 (1), F4 (b3).
Dm open strings: fourth string, D (D3).
Gm
Gm frets from the sixth string to the first: 3 1 0 0 3 3.
Gm spelling: G, Bb, D.
Gm sounding notes: G2 (1), Bb2 (b3), D3 (5), G3 (1), D4 (5), G4 (1).
Gm open strings: fourth string, D (D3), third string, G (G3).
C#m
C#m frets from the sixth string to the first: x x 2 1 2 0.
C#m spelling: C#, E, G#.
C#m sounding notes: E3 (b3), G#3 (5), C#4 (1), E4 (b3).
C#m open strings: first string, high E (E4).
Open dominant 7 chords
E7
E7 frets from the sixth string to the first: 0 2 0 1 0 0.
E7 spelling: E, G#, B, D.
E7 sounding notes: E2 (1), B2 (5), D3 (b7), G#3 (3), B3 (5), E4 (1).
E7 open strings: sixth string, low E (E2), fourth string, D (D3), second string, B (B3), first string, high E (E4).
A7
A7 frets from the sixth string to the first: x 0 2 0 2 0.
A7 spelling: A, C#, E, G.
A7 sounding notes: A2 (1), E3 (5), G3 (b7), C#4 (3), E4 (5).
A7 open strings: fifth string, A (A2), third string, G (G3), first string, high E (E4).
D7
D7 frets from the sixth string to the first: x x 0 2 1 2.
D7 spelling: D, F#, A, C.
D7 sounding notes: D3 (1), A3 (5), C4 (b7), F#4 (3).
D7 open strings: fourth string, D (D3).
G7
G7 frets from the sixth string to the first: 3 2 0 0 0 1.
G7 spelling: G, B, D, F.
G7 sounding notes: G2 (1), B2 (3), D3 (5), G3 (1), B3 (3), F4 (b7).
G7 open strings: fourth string, D (D3), third string, G (G3), second string, B (B3).
C7
C7 frets from the sixth string to the first: x 3 2 3 1 0.
C7 spelling: C, E, G, Bb.
C7 sounding notes: C3 (1), E3 (3), Bb3 (b7), C4 (1), E4 (3).
C7 open strings: first string, high E (E4).
C7 leaves out G.
B7
B7 frets from the sixth string to the first: x 2 1 2 0 2.
B7 spelling: B, D#, F#, A.
B7 sounding notes: B2 (1), D#3 (3), A3 (b7), B3 (1), F#4 (5).
B7 open strings: second string, B (B3).
× mute · ○ open · green root · terracotta other chord tones
Numbers show a suggested finger: 1 index · 2 middle · 3 ring · 4 pinky. A bar means one finger holds several strings. Frets run from the sixth string, low E, to the first string, high E.
Why the open strings belong
An open string in this chart is already a note of that chord, so it rings without a finger stopping it. That is the practical difference from a barre, where every sounding string is fretted.
Shapes left off the chart
7 other open-position finder shapes stay off this chart so each pitch keeps one spelling. 5 can be named here: D# at 3 1 1 0 x x; Cm at x 3 1 0 1 3; D#7 at x x 1 0 2 3; F7 at 1 0 1 2 1 1; F#7 at 0 1 2 3 2 2. 2 more stay unnamed because the root name would spell a pitch this chart already writes another way.
A measured E major
The three strongest pitch classes in the E major recording were E, B and G#.
The loudest G#3 peak is 212.69 Hz. Equal temperament puts G#3 (MIDI 56) at 440 × 2^((56 − 69) ÷ 12) = 207.65 Hz. Cents are 1200 × log2(212.69 ÷ 207.65) = 41.5 cents.
The low E peak in the same window is 83.07 Hz, against E2 (MIDI 40) at 82.41 Hz, which is 13.9 cents.
The clip is an acoustic guitar E major, public domain, recorded by WBOSITG and published as Wikimedia Commons File:E-major.ogg. Hear on this page uses the site's sampled guitar, not that recording.
Where the beginner page fits
Guitar chords for beginners is the practice page for Em, E, Am, A, D, G, C and Dm. This open chords page is the inventory: which roots have an open major, minor, or dominant 7, and which open strings sound. Guitar chords for beginners is the practice route. How to read guitar chords explains the X and O marks. The minor side has its own page: minor chords lists all twelve roots and every chord in a minor key.
Questions people ask about open chords
Are open chords just the beginner shapes?
The beginner page stops at Em, E, Am, A, D, G, C and Dm and then drills the changes. This page keeps going through every open-position major, minor, and dominant 7 the finder can spell with one name per pitch.
Why do open chords sound the way they do?
An open string in this chart is already a note of that chord, so it rings without a finger stopping it. That is the practical difference from a barre, where every sounding string is fretted.
Is that F the barre F?
No. F on this chart is 1 0 3 2 1 1. Open strings: fifth string, A (A2). The first F major in the finder with no open string is 1 3 3 2 1 1.
What is the cents number?
The loudest G#3 peak is 212.69 Hz. Equal temperament puts G#3 (MIDI 56) at 440 × 2^((56 − 69) ÷ 12) = 207.65 Hz. Cents are 1200 × log2(212.69 ÷ 207.65) = 41.5 cents.