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What does 5/7 mean in a chord chart?

By Adrian · 8 October 2026 · 7 min read

5/7 means: play chord 5, with the 7th note of the key in the bass. It looks complicated, but honestly, my students rarely get it wrong. I explain what the notation means, show it in a song, and that's it.

(If the numbers are new to you, start with Nashville numbers explained.)

Read it in two parts

A slash chord has two parts. Before the slash: the chord. After the slash: the lowest note, the one in the bass.

• In numbers, 5/7 is chord 5, with the 7th step of the key in the bass.
• In letters, in C, that's G/B: a G chord, with B in the bass.

The same goes for the others you'll meet: 1/3 is chord 1 with the 3rd step in the bass (C/E in C), and 4/1 is chord 4 with the 1st step in the bass (F/C in C). The only mistake I sometimes see is a student forgetting the bass note and playing a plain chord. It happens, but rarely.

Why the bass note is there

Most of the time, a slash chord amplifies a feeling that's already there: the movement, or even the tension. When you see one in a chart, try to understand why it's there. Usually it's one of three reasons.

1. A stronger pull

5/7 puts the 7th note of the key in the bass, the note right under home. When it goes to 1, the bass only has one small step left, and you can hear it pulling:

2. Moving forward more expressively

Listen to 1 going to 6m, first with a plain 5 in the middle, then with 5/7:

3. The bass stays where it is

Sometimes the slash chord does the opposite: the chord changes, but the bass stays on a note both chords share. F and C share the note C, so 4/1 lets the bass sit still while the harmony moves above it:

Either way, slash chords give us the chance to create countermelodies. Simply by using different notes in the bass, we add one more layer to our arrangement. It's a useful tool.

How to play it

To keep things simple at first, I ask my students to play the bass note with the left hand, twice: as an octave. The right hand fills in the rest of the chord.

• G/B in C: left hand B and the B an octave above, right hand G, B, D.
• C/E: left hand two Es, right hand C, E, G.

That's all it takes. The left hand plays the note after the slash, the right hand plays the chord before it.

In a band

What if there's a bass player? I usually ask the pianist to respect the bass note too, even when the bass player plays it. It's not hard, and the keys and the bass then tell the same story.

Be Thou My Vision, with and without the bass notes

You may know this one from Minor chords in a major key: Be Thou My Vision in D. This time it has slash chords: G/D (4/1), A/C♯ (5/7), and D/F♯ (1/3), which comes back three times. You'll find all three reasons in it: in line 1, G/D keeps the bass on D, and A/C♯ pulls into D.

Switch between plain chords and slash chords, and listen to the bass. The chords in gold are the ones that change. In line 2, the slash chord turns the bass into a little melody of its own: E, F♯, G, A, climbing step by step under the tune.

The melody and the chords are the same in both versions. Only the bass changes, and with it, the whole verse moves differently.

Make your own bass line

Most of my students don't add slash chords themselves; they play them when they see them in the chart. But I'd recommend it. Slash chords are as valuable and useful a tool as adding extensions and suspensions.

Start by paying attention to slash chords whenever they appear in a chart, and try to understand the reason: a stronger pull, moving forward, or the bass staying put. Once you understand the different reasons they're there, at some point you'll feel the need to use them yourself. Here's one way to start: take 1 4 5 1 and let the bass walk.

Pianists have told me that when I use slash chords very often, it starts to sound like a walking bass. They were fascinated, because it completely changes the character of a song, and above all its foundation.

Next: every number starts from 1. Learn to find it by ear in How to find the key of a song by ear.