free chord tool.

chords to roman numerals.

Type or paste your chords and see each chord's number in a key and mode. It reads all eight modes, keeps sevenths and slash chords, and takes a whole song with its words. It is free, with no signup.

Chords start with a capital letter. Write them on one line like Am F C G, in rows like | Am F | C G |, or paste a song with the chords above the words or in [brackets].

what do the numbers on a chord mean?

A chord's number says which note of the key it is built on. In A minor, Am is i, F is VI, C is III and G is VII. Capitals are major chords, lower case is minor, and ° marks a diminished chord. The numbers stay the same when the song moves to another key, which is why musicians use them to compare songs.

how can you tell the key from the chords?

Look for the chord the song feels at home on, often the first and the last, then check that the other chords belong to the same scale. Am F C G fits both A minor and C major; it starts on Am, so A minor is the better reading. This page makes that guess for you and lets you change it.

what changes in another mode?

The same chords can get the same numbers and still not fit. Am F C G is i VI III VII in A minor and in A phrygian, but G major is not in A phrygian. This page reads your chords in all eight modes and marks every chord that does not belong.