Read a Chord Line

Type the chords as a chart writes them. The reader finds the key and mode, writes every chord as a Roman numeral, and labels each move a chord makes — all in your browser, with nothing sent anywhere.

Chord symbols separated by spaces, commas or bar lines; a slash names a bass note.

Or read one of the eight lines the corpus takes from its sources:

Read in C major

Nine chords read: six fit C major and three have a note outside it; the line opens and closes on its tonic chord. Score 5.

C E7 Am F Fm C D7 G7 C — each chord as read in C major: its Roman numeral, whether every note is in the key, and the moves it makes.
Chord Numeral In the key? Moves
C I in the key —
E7 III7 outside: G# V/vi
Am vi in the key —
F IV in the key —
Fm iv outside: Ab minor iv
C I in the key —
D7 II7 outside: F# V/V
G7 V7 in the key —
C I in the key —

Three moves found: V of vi at E7 Am (III7–vi), the minor iv at Fm (iv) and V of V at D7 G7 (II7–V7).

Typing a line

Write the chords the way a chart or a lead sheet does: C, Am, G7, Fmaj7, Bm7b5, Dsus4, with b and # for flat and sharp and a slash for a bass note (C/E). Spaces, commas and bar lines all separate one chord from the next. Anything that is not a chord symbol, such as a repeat sign or N.C., is listed under the table as not read and left out of the score; the reader never guesses what a stray token might have meant.

Reading the table

Each row is one chord of your line. The numeral is counted from the major scale on the tonic of the key the line is read in, whatever its mode, so in A minor the F chord is written bVI and the E minor chord is v. Upper case is a major chord, lower case a minor or diminished one, and a seventh or other extension keeps its own suffix. The next column says whether every note of the chord belongs to the key; when one does not, it names the note. The last column carries each move the chord makes, and each label links to the page for that move, where its rule is written out step by step.

When the key is a tie

Two or three chords rarely settle a key on their own, so short lines often score the same in several keys at once. The reader names every one of them above the table and reads the line in the first, by the order set out on the moves page; a button for each tied key reads the same line again in that key, and the numerals and moves change with it.

What the reader leaves out

It reads chord symbols and nothing else: no melody, no rhythm, no bar lengths. It finds one key for the whole line, so a line that settles somewhere new halfway through is read as a single key, and the chords after the shift show up as outside it. Your line is read in this browser, never stored, and never becomes part of a web address.