Natural vs Harmonic vs Melodic Minor: Two Notes, Three Scales

"This piece is in A minor" sounds complete until you read the score: a G♯ in one bar, an F♯ a few bars later, both gone in a descending run. Three minor scales are taking turns. This guide puts them on one tonic, shows why each exists and gives you a 15-minute piano drill for AP Music Theory, ABRSM or audition prep.

What is a minor scale?

A minor scale puts its 3rd degree three half steps above the tonic (major: four). That minor third gives minor its darker color.

The easiest one is A natural minor: every white key from A to A, the same notes as its relative C major. Natural minor is identical to the Aeolian mode. Its degree formula is written against the major scale: 1 2 ♭3 4 5 ♭6 ♭7.

Natural, harmonic and melodic minor in one table

All three scales are built on A, so you can see exactly which note moves.

The pattern in one sentence: the first five degrees never change. Everything happens on the 6th and 7th, so to identify a minor scale you only need to check those two notes.

What is the harmonic minor scale, and why does it exist?

Natural minor has no leading tone. In C major, B sits a half step below C and pulls the ear home. In A natural minor the 7th is G, a whole step below A. The chord on the 5th degree becomes Em, and the cadence loses its sense of arrival.

The fix is to raise the 7th a half step. G becomes G♯, and three things follow:

• There is a leading tone: G♯ is a half step below A.
• The V chord turns major: E–G♯–B (E). Add a seventh and you get E7, so V7–i sounds as strong in minor as in major.
• A vii° chord appears: G♯–B–D. This is also where the fully diminished seventh (G♯°7) comes from, covered in the seventh chords guide.

The side effect is a gap of three half steps between F and G♯, an augmented second, which classical voice leading usually avoids in a melody. Hence the name: the scale exists for harmony, to make V major. Wikipedia's Minor scale article describes the raised 7th as the first fix for the missing leading tone and explains why the augmented second is awkward in a melody.

What is the melodic minor scale, and why does it change on the way down?

Melodic minor closes the augmented second by raising the 6th too: A–B–C–D–E–F♯–G♯–A. No gap is larger than a whole step and the leading tone stays.

In the classical tradition both notes drop back on the way down, returning to natural minor: A–G–F–E–D–C–B–A. Raised notes pull upward toward the tonic; a descending line doesn't need that pull. The Minor Scales page from Puget Sound's Music Theory for the 21st-Century Classroom shows with notation that descending melodic minor is the same as natural minor.

In jazz, melodic minor is played the same both ways and is often called the jazz minor scale; its modes include Lydian Dominant and Altered, as Wikipedia's Jazz minor scale article lists. A classical harmony exam expects the descending natural form.

How do you tell which minor scale it is in 4 steps?

1. Find the tonic. The note or chord a piece ends on is usually the tonic. For a method that works from the chords, see how to find the key of a song.
2. Check the 3rd degree. Three half steps above the tonic (C over A) means minor. Four half steps (C♯) means major.
3. Check the 7th degree. G natural means natural minor or descending melodic minor. G♯ means harmonic or ascending melodic minor.
4. Check the 6th degree. G♯ with F natural is harmonic minor. G♯ with F♯ is melodic minor.

One piece can use all three, so ask "which minor is this passage using?" rather than "which minor is this piece in?"

What are the chords of the harmonic minor scale?

Minor-key harmony usually takes its chords from harmonic minor, home of V and vii°.

Minor chords take lowercase numerals (i, iv), major chords uppercase (V, VI). In practice III+ is rare. The 3rd-degree chord in a minor key usually comes from natural minor and is major (C). The logic behind Roman numerals is covered in functional harmony explained.

How does Michord show the three minor scales, and what doesn't it do?

Michord's Scales & Modes feature writes the notes you play on the staff in scale order. It names the scale or mode from 54 options and shows the degree formula once you've played the whole scale. You can play on a MIDI keyboard, the on-screen piano or your computer keyboard. To compare the three minors:

• Starting on A, play A–B–C–D–E–F–G. The label reads A Minor (Aeolian) · 1 2 ♭3 4 5 ♭6 ♭7.
• Change G to G♯. The label reads A Harmonic Minor · 1 2 ♭3 4 5 ♭6 7.
• Change F to F♯ as well. The label reads A Melodic Minor · 1 2 ♭3 4 5 6 7.

To guess the tonic, Michord looks at the first note you play, then the lowest, so start on A or the same white keys may read as C major. Skip a degree and the possible scales appear with a question mark; hovering shows each formula. The app doesn't look at direction: descending classical melodic minor shows as natural minor, which is correct because the notes are the same. You can play the result back at 60 BPM.

Michord doesn't listen to recordings or audio files, so it is not a scale finder from audio. The analysis is rule-based, not AI. It's a desktop app for macOS (Apple Silicon) and Windows, with no phone or tablet version.

How do you practise minor scales on piano in 15 minutes?

1. One tonic, three scales (5 min). Play natural, harmonic and melodic minor on A, ascending, back to back. Change only the 6th and 7th each time and say out loud which one you changed.
2. The two-note test (5 min). Do the same in D minor and E minor. D harmonic minor needs C♯; E harmonic minor needs D♯. Write each scale down first, then play it.
3. Hear it in a cadence (5 min). Play Am–Dm–E–Am (i–iv–V–i), then make V minor (Em) and hear why the leading tone matters.

If you're preparing for an audition, add this routine to the weekly plan in music school audition preparation.

How can teachers explain minor scales in class?

Present them as one scale with two switches, the 6th and the 7th: students keep A–B–C–D–E fixed and move only the last two notes. With the screen projected, the class sees the label change the moment ♭7 becomes 7. Screen recording with audio, also in the subscription, lets you keep the lesson.

Conclusion

Minor is a family with two movable notes. Check the 6th and 7th: both low is natural, only the 7th raised is harmonic, both raised is melodic.

Frequently Asked Questions (FAQ)

What is the difference between natural and harmonic minor?

One note: harmonic minor raises the 7th a half step. A natural minor is A–B–C–D–E–F–G; A harmonic minor is A–B–C–D–E–F–G♯, which gives a leading tone and a major V chord (E).

Why does melodic minor change on the way down?

In classical usage it raises the 6th and 7th going up (A–B–C–D–E–F♯–G♯) and returns to natural minor going down, because the raised notes only pull upward toward the tonic. In jazz it is played the same both ways (the jazz minor scale).

Why does harmonic minor have an augmented second?

Raising the 7th opens a gap of three half steps between the 6th and 7th degrees: F to G♯ in A minor. That interval is an augmented second. Melodic minor closes the gap by raising the 6th as well.

What are the chords of the harmonic minor scale?

In A harmonic minor the triads are i (Am), ii° (B°), III+ (C augmented: C–E–G♯), iv (Dm), V (E), VI (F) and vii° (G♯°). The major V and the diminished vii° in minor keys come from this scale.

Can Michord tell me which minor scale I'm playing, and is it free?

Yes. Scales & Modes names what you play from 54 scales and modes with its degree formula (e.g. A Harmonic Minor · 1 2 ♭3 4 5 ♭6 7). It is part of the subscription: 2.99 USD/month or 22.99 USD/year. The permanent free plan needs no card and includes all input methods, a real grand piano sound and note names. Michord does not listen to audio.