Finding songs that share a progression

When two songs use the same chord movement, your hands already know part of the second song. That makes shared progressions a useful way to find material for a practice session, a medley, or the next place to go in a set.

The chord names do not have to match. G–D–Em–C and C–G–Am–F have the same interval pattern in different keys, so chordlist can place the songs together after normalising their progressions.

What normalising means

For each comma-separated progression, chordlist shifts the first chord to a common reference note and moves the remaining chords by the same number of semitones. These two lines therefore produce the same normalised result:

G D Em C  →  C G Am F
C G Am F  →  C G Am F

Whitespace does not affect the comparison, and a progression beginning on a minor chord is given a minor reference instead. Chord order and chord quality still matter:

G D Em C   matches C G Am F
G D C Em   does not match G D Em C
G D Em7 C  does not match G D Em C

This is an exact comparison after transposition, not a general judgement that two songs sound similar. It does not infer substitutions, ignore a passing chord, rotate the loop, or decide that two different sections are close enough.

Multiple sections must line up

Commas split the chords field into separate progressions. A song can record a verse and chorus like this:

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chords: G D Em C, C G D Em
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Each section is normalised from its own first chord, and the complete sequence is compared. Another song matches only when it has the same number of sections with the same chord order and qualities after normalisation.

That strictness keeps the suggestions predictable. It also means two songs can share a verse loop without appearing as matches if their choruses differ. Record the level of detail that is useful to you: a single central loop for broad grouping, or several comma-separated sections for narrower matches.

The file format guide documents the field. If Roman numerals would make the relationship easier to see, compare the three notation systems.

Find the suggestions

Once a valid progression is stored, songs with the same normalised value appear as suggestions on the song detail view. A song without a parseable first chord cannot be normalised, so use ordinary chord symbols such as F#m, Bb, or C/G rather than prose in the field.

The progression does not need to be in the same key as the song you are viewing. Matching is about the movement between chords, not the absolute names.

Build a short set

Use the matches as a harmonic shortlist:

1. Open a song you can already play comfortably.
2. Check the matching-progression suggestions beneath it.
3. Open a candidate and play the final loop of the first song into the opening of the second.
4. Adjust the viewed transposition if the vocal range or transition needs another key.
5. Write down the order once the hand-off works without stopping.

The playing guide covers suggestions, transposition, and moving back through songs opened during the current session. If you need a progression to practise first, I–V–vi–IV is a useful starting point.

Treat a match as a starting point

The same harmony does not guarantee a smooth segue. Tempo, metre, groove, melody, lyrical mood, and vocal range can all pull two songs apart. A normalised match also says nothing about whether the original keys are comfortable for the same singer.

That is why the suggestions work best as a filter rather than an automatic setlist. They reduce a large library to songs worth trying with your instrument in hand. The final decision still belongs to your ear—and to the room you are trying to keep moving.