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What the Two Numbers in Music Tell You · Rhythm & Time · time signature · meter

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What the Two Numbers in Music Tell You

with Melody

Melody stands at a chalkboard in a cozy music classroom, pointing enthusiastically at two large stacked numbers drawn in chalk, while colorful music notes float around her and a drum kit sits in the corner.

Identify the top and bottom numbers of a time signature on a piece of sheet music.
Explain what the top number tells a musician about beats in a measure.
Explain what the bottom number tells a musician about which note gets one beat, using the note-value number system.
Compare how 4/4 and 3/4 time feel different when clapping or tapping along.
Identify how many beats are in a measure and which note gets the beat for 2/4, 3/4, and 4/4 time signatures.

Key terms

time signature: Two stacked numbers at the music start.
measure: A small box of beats in music.
beat: One steady count in the music.
top number: It tells how many beats per measure.
bottom number: It tells which note gets one beat.

Two Stacked Numbers

Near the very start of a piece of music, you will find two numbers stacked one on top of the other, like a tiny tower. This pair of numbers is called the time signature. It is a secret code that tells musicians how to count the music. One number sits on top and one sits on the bottom, and each number has its own special job. Once you know what each number means, you can read any time signature you ever see. It is like cracking a fun code together!

The Top Number Counts Beats

The top number has an easy job. It tells you how many beats go inside each measure. A measure is a little box of music marked off by lines, kind of like a box that holds a set number of beats. If the top number is 4, then you count four beats in each box: one, two, three, four. If the top number is 3, you count three beats in each box: one, two, three. So just look at the top number and that is how many counts you put in every measure before starting again.

The Bottom Number Picks the Note

The bottom number tells you which kind of note gets one beat. Musicians use a number code for notes. A whole note is 1, a half note is 2, a quarter note is 4, and an eighth note is 8. So when the bottom number is 4, that means the quarter note gets one beat. In four-four time you count four beats and the quarter note gets the beat, like a steady marching song. In three-four time you count three beats and it feels like a swaying waltz dance. Try tapping the strong beat one the loudest!

Worked examples

How many beats are in a 3/4 measure?

Look only at the top number, which is 3.
The top number tells how many beats per measure.
So each measure has three beats.

Answer: 3 beats.

In 4/4 time, which note gets one beat?

Look at the bottom number, which is 4.
In the note code, the number 4 means a quarter note.
So the quarter note gets one beat.

Answer: A quarter note.

Hey there! I'm Melody, and today we're cracking a secret code that every piece of written music uses. At the start of a piece of sheet music, after the clef symbol (the swirly sign at the far left of each line of music) and the key signature (the sharps or flats shown there — or nothing at all if the piece is in C major!), you'll spot two numbers stacked on top of each other — like two numbers sitting in a tower, one above the other. That pair of numbers is called the TIME SIGNATURE, and it appears near the very beginning of the music. The TOP number answers the question: how many beats fit inside one measure? A measure is a small chunk of music separated by bar lines, like a box. If the top number is 4, you count 4 beats per box. If it's 3, you count 3 beats per box. Simple! The BOTTOM number answers the question: which kind of note gets exactly one beat? Here's the code key — musicians use a special number system for note values. A WHOLE note (worth a full measure in 4/4) is represented by 1. A HALF note is represented by 2. A QUARTER note is represented by 4. An EIGHTH note is represented by 8. The bottom number just tells you which of those notes takes up exactly one beat. So a 4 on the bottom = quarter note gets the beat. A 2 on the bottom = half note gets the beat. An 8 on the bottom = eighth note gets the beat. Once you know the number system, any time signature you ever meet will make sense! So 4/4 time (say "four-four") means: 4 beats per measure, and a quarter note lasts one beat. That's the most common time in pop music — think of a steady ONE-two-three-four, ONE-two-three-four. And 3/4 time means: 3 beats per measure, quarter note gets the beat. That's the waltz — ONE-two-three, ONE-two-three. It has a swaying, dancing feel. Here's a hint for the activity: tap your foot on beat ONE the loudest, and tap softer for the other beats — or clap your hands, or nod your head if that's easier for you. That strong-soft pattern helps your body feel the time signature!

Activity

Match each time signature card to the picture that correctly shows its beats per measure and which note gets the beat.

Practice

Clap four steady beats for a measure of 4/4 time.

Tap a swaying waltz of three beats for 3/4 time.

Common mistakes to avoid

The bottom number counts beats.The top number counts beats; the bottom names the beat note.
The bottom number means measures.The bottom number tells which note gets one beat, not measures.

Check your understanding

A song is written in 3/4 time. How many beats are in each measure?

In 4/4 time, the bottom number is 4. What does that tell you?

Look at a time signature written as 2/4. Which statement is correct?

Recap

A time signature is two stacked numbers at the start of music. The top number tells how many beats are in each measure. The bottom number tells which note gets one beat, using a code where 4 means a quarter note.

Reflect

Would you rather march in 4/4 or sway in a 3/4 waltz?