Have you ever looked the beginning of a piece of music and noticed that there are a few numbers written? Maybe you’re one of those people who like music because it’s NOT math so you were shocked to see numbers. Don’t worry, these numbers aren’t difficult to figure out. They’re called the time signatures.

In reality, music is based largely on math. When we speak of rhythm, all rhythms, unless stated otherwise by the composer, are meant to be exact. Quarter notes are exactly twice as fast as half notes and so on. You get the picture.

The time signature tells you two key pieces of information. The top number is the easy number to understand. It tells us how many beats are in each measure. To make it easier on the reader, music is broken up in to measures. Those lines that make your music in to a series of small boxes with information inside each of them is a measure. Each of those has the same amount of beats.
The top number can be anything but to be practical, the number must remain small. Normally, we see a “4” as the top number meaning there are 4 beats in every measure but the number can be much higher or lower. If the number is a “4” then each measure will contain 4 beats. That can be accomplished in many different ways: 4 quarter notes, 2 half notes, 1 whole note, 16 sixteenth notes, or any combination imaginable.

The bottom number is a little more tricky. It tells us what kind of note IS one beat. First you need to know the secret code:

1 = Whole Note
2 = Half Note
4 = Quarter Note
8 = Eighth Note
16 = Sixteenth Note

There are a few more numbers that can be used for the bottom number of the time signature but they aren’t overly practical. As you can see, the bottom number can’t be any number. It can only be certain numbers because these numbers are a secret code for a certain kind of note.

Here’s one way to figure this out. Let’s say that your time signature has a 4 on the top and a 4 on the bottom.(Expressed in a fraction without the middle line) Fill in this Sentence with each number:

“There are _____ ________________ notes in every measure.”

So if you fill in the blanks, here’s how it reads:

“There are “4” “Quarter” notes in every measure.”

All we did was place the first number in the first blank and then we used our secret code for the second number. This tells us that each measure has 4 quarter notes or some combination that equals 4 quarter notes (2 half notes, 16 sixteenth notes, etc.)

Why is the bottom number important? What if the time signature had a 4 on the top and 2 on the bottom? (Here’s where the math comes in to play.) That “2” doubles the amount of information that can be contained in a measure when we compare it to 4/4, our earlier time signature. Since there can be 4 half notes in a measure in 4/2, we can put 8 quarter notes in the measure.

Sure, it’s a little complicated but with a little practice, you understand it!