How to Read a Chord Name — And Build Any Chord You See

Ever looked at a chord chart and seen something like Fm7b5 or Bbmaj9 and thought — what on earth does that mean? You’re not alone. Chord names look like a secret code at first. But once you know the rules, they make total sense. Every part of a chord name is telling you something specific. Let’s break it down piece by piece, starting from the very beginning.

What Even Is a Chord?

A chord is just three or more notes played at the same time. That’s it. The notes aren’t random though — they’re chosen based on a formula. And every chord name is just a shorthand for that formula.

Think of it like a recipe. The chord name tells you which ingredients to use. Once you know the recipe, you can cook up any chord in any key.

It All Starts With the Major Scale

Every chord formula is built on top of the major scale. So before we talk about chords, we need to talk about the major scale for just a second.

The major scale has 7 notes, and each one has a number called a scale degree. In the key of C, those notes are:

Degree	1	2	3	4	5	6	7
Note in C	C	D	E	F	G	A	B

These numbers are the same system used to name every chord ever written. When you see a number in a chord name — like the 7 in Cmaj7, or the 9 in G9 — it’s referring to one of these scale degrees. Keep that in mind as we go.

The Major Triad: The Starting Point for Everything

The most basic chord in all of music is the major triad. It uses three scale degrees: 1, 3, and 5.

That’s what you see when a chord name is just a letter on its own. A plain C means C major. A plain G means G major. No extra symbols, no extra notes — just the 1st, 3rd, and 5th notes of the major scale built on that root.

The major triad sounds bright and happy. It’s the most common sound in all of Western music. Almost every other chord is a variation of this starting point.

The Minor Triad: One Small Change, Very Different Feeling

To turn a major chord into a minor chord, you lower the 3rd by one half step. That one tiny change makes the whole chord sound darker and more emotional.

When you see a lowercase m after a chord name — like Am or Dm — that’s the minor chord. Same root, same 5th, but the 3rd is one half step lower. That’s the only difference between major and minor.

Diminished and Augmented: The Other Two Triads

There are two more types of basic triads. Both are built by tweaking the 3rd and 5th of the major chord.

Diminished — Everything Gets Smaller

A diminished chord lowers both the 3rd and the 5th by a half step each. It sounds tense and unstable — like something is about to go wrong. You’ll see it written as C° or Cdim.

Augmented — The 5th Gets Bigger

An augmented chord raises the 5th by a half step. The result sounds dreamy and unresolved — kind of like something floating in mid-air. You’ll see it written as C+ or Caug.

What Do the Numbers in Chord Names Mean?

Once you go beyond a basic three-note triad, chord names start including numbers. The rule is simple:

The number tells you which additional scale degree to stack on top of the triad.

The 7th Chords: Adding One More Note

A 7th chord takes a basic triad and adds the 7th scale degree on top. There are several types depending on whether the 7th is lowered or not — and whether the triad underneath is major or minor.

Dominant 7 (just “7”)

When you see a plain number 7 — like G7 or C7 — that’s a dominant seventh chord. It’s a major triad plus a lowered 7th. This chord has a strong pull toward the root chord and shows up constantly in blues, jazz, and pop.

Major 7 (maj7)

The major 7 chord uses the full natural 7th — not lowered. It sounds lush and sophisticated. The key thing to remember: maj7 uses the natural 7th, while a plain 7 uses the flat 7th. That distinction matters a lot.

Minor 7 (m7)

A minor triad with a flat 7th on top. The workhorse of jazz and R&B. Cool, relaxed, and slightly melancholy.

Minor Major 7 (mMaj7)

A minor triad with the natural (major) 7th instead of the flat 7th. Sounds mysterious. Heard a lot in film scores and bossa nova.

Half Diminished / Minor 7 Flat 5 (m7b5)

A diminished triad with a flat 7th added. Dark and unresolved. Used heavily in jazz and minor key music. Called “half diminished” because the 7th is only flattened once instead of twice.

Fully Diminished 7 (°7)

Every note is flattened — including the 7th, which gets lowered twice (a double flat, written as bb7). The result is a completely symmetrical chord that sounds equally unstable no matter which note you call the root. Eerie and tense.

Suspended Chords: Replacing the 3rd

Suspended chords — or “sus” chords — replace the 3rd with either the 2nd or the 4th scale degree. There’s no 3rd at all, which means they’re neither major nor minor. They sit in harmonic limbo — open and unresolved, waiting for somewhere to go.

You hear sus chords constantly in pop and rock — often right before a major or minor chord resolves. They create a great moment of pause and anticipation.

The 6th Chords: A Sweeter Alternative

Instead of stacking up to the 7th, a 6th chord adds the 6th scale degree on top of a triad. It sounds warmer and less tense than a 7th chord — more like a smile than a dramatic moment.

Notice the 6th itself doesn’t change between major and minor 6th chords — only the 3rd changes. The minor 6th has a particularly bittersweet quality you’ll hear in jazz standards and film scores.

Going Beyond 7: The 9th, 11th, and 13th Chords

When chord names go above 7, they’re referring to notes in the second octave of the scale. Think of it like this — after you run through 1 through 7, you keep counting into the next octave:

Extended degree	9	11	13
Same as…	2 (up an octave)	4 (up an octave)	6 (up an octave)

The reason we use the bigger numbers is important: these notes go on top of the 7th chord, not instead of it. A 9th chord includes the 7th. A 13th chord includes everything below it too.

The 9th Chord

A 9th chord is a 7th chord with the 9th added on top. When you see a plain 9 — like G9 or C9 — it means a dominant 7th chord plus the 9th. Five notes total.

The Add9 Chord: 9th Without the 7th

The add9 chord adds just the 9th directly to the triad — skipping the 7th entirely. That’s why it says “add.” You’re adding one note without building the full 7th chord first. The result is open and airy without being too jazzy or complex. Probably the most popular color chord in modern pop and rock.

Flat and Sharp Signs in Chord Names

Sometimes chord names include a flat (b) or sharp (#) symbol followed by a number — like m7b5 or 7#9. These are called alterations. They tell you to lower or raise one specific note by a half step.

• b5 — lower the 5th by a half step (diminished 5th)
• #5 — raise the 5th by a half step (augmented 5th)
• b7 — lower the 7th by a half step (the minor/flat 7th)
• b9 — lower the 9th by a half step (tense and bluesy)
• #9 — raise the 9th by a half step (the famous “Hendrix chord” uses this)
• #11 — raise the 11th by a half step (gives a dreamy, floating Lydian sound)

You read the chord name left to right, applying each instruction as you go. So Cm7b5 means: C minor (Cm) + flat 7 (m7) + flat 5 (b5). That gives you C + Eb + Gb + Bb. Simple once you know the parts.

Inversions: Same Notes, Different Order

An inversion just means you’ve changed which note is at the bottom of the chord. The notes are all the same — you’re just rearranging who’s lowest.

• Root position — the root note is on the bottom. C major: C E G.
• 1st inversion — the 3rd is on the bottom. C major: E G C.
• 2nd inversion — the 5th is on the bottom. C major: G C E.
• 3rd inversion — only on 7th chords. The 7th is on the bottom.

Inversions are used all the time in piano playing to keep the bass line smooth. Instead of jumping around, you move from chord to chord with the smallest possible distance between notes. The chord identifier tool above will tell you when you’re playing an inversion so you can start recognizing them by ear and by feel.

How to Use the Chord Identifier Tool Linked Above

Now that you know how chords are built, you might want to play around with some notes to see what chords you can come up with. Here’s how to get the most out of the tool:

• Click the notes you’re playing — you don’t have to click them in any particular order. The tool figures out the chord from the combination of notes, not the order you clicked them.
• Set the key context — if you’re playing in a flat key like Bb or Eb, set that as your key. The tool will use flat note names so the results match what you’d see on a real chord chart.
• Try incomplete chords — if you only play two notes of a chord, the tool will show “Possible — incomplete” results with the missing note listed in orange. This is useful for figuring out what a partial voicing is.
• Look at “Also matches” — sometimes a set of notes matches more than one chord name. The tool shows all valid interpretations so you can pick the one that makes sense in context.
• Use it to learn — play a chord you already know, identify it with the tool, then read the formula. Over time you’ll start to see the patterns and recognize chord types by ear.