Two-chord voice-leading calculator

What the table tells you

Each row is one voice. The before note is where that voice sits in the starting triad, the after note is where it lands in the chosen target inversion, and the motion value counts semitones. A positive value means the voice rises, a negative value means it falls, and zero means a pitch is shared between the two chords and stays put. The total of the absolute motions is the score the calculator minimizes, so a smaller total usually means the chords connect smoothly.

Why small movement helps

When voices move by small steps, the progression sounds connected and each line is easier to follow by ear. Large leaps make the change feel abrupt. Looking at the shared notes is especially useful, because a common tone is a point of continuity that you can hear while the other voices move around it. This habit trains you to listen for which pitches carry over, which is the core skill behind reading harmony in a progression.

What the calculator does not decide

The tool considers only a small ordered search of triad inversions in neighboring octaves. It does not judge counterpoint rules, hand reach or the stylistic appropriateness of a connection, and it is not an optimizer for a whole composition. Treat the result as one useful option among many, and compare it with what your ear and your musical goals suggest. Use the steps below to predict, calculate and compare.

Try it step by step

1. Set Root / tonic to C and Starting quality to major so the first chord is C major, the triad C, E and G.
2. Set Target root to F and Target quality to major, then run the calculator and read the table. Note which pitch stays in place and which voices rise or fall.
3. Change Target root to A and Target quality to minor, keeping the start at C major. Before you read the table, predict which pitches are shared between C major and A minor, then compare your prediction with the result.
4. Use the audio playback option from the tool's controls to hear the single example, and listen specifically for the shared notes while the other voices move. For practice on a physical instrument, play both triads yourself at the piano or keyboard and move only the voices shown in the table.

A concrete example

Starting from C major (C4, E4, G4) and targeting F major, the calculator can connect C4, E4, G4 to C4, F4, A4. The bottom C stays (0 semitones), E rises one semitone to F (+1), and G rises two semitones to A (+2). The total movement is 0 + 1 + 2 = 3 semitones. Here the common tone is C, which is the shared pitch between the two chords.

A common wrong turn

Judging a connection only by the total movement number and ignoring which voices are actually moving. Two connections can share the same total while one keeps a common tone and the other moves every voice.

Try this instead: Read the motion column row by row. Identify the shared pitches first, then check whether the moving voices take small steps. Listen to the result, because the ear shows continuity that a single total cannot.

Where to go next — and why