How time signatures work: reading the top and bottom numbers
At the start of every piece, right after the clef and key signature, there are two numbers stacked on top of each other. That's the time signature. It tells you how the music is organized into measures and which note gets the beat. Read it before you play a single note, because it changes how you count everything that follows.
The top and bottom numbers
A time signature looks like a fraction, but it isn't one. Each number has its own job:
- The top number tells you how many beats are in each measure.
- The bottom number tells you which kind of note gets one beat.
So 3/4 means three beats per measure, and the quarter note gets the beat. Every measure adds up to exactly three quarter notes' worth of music, whether that's three quarters, a dotted half, or six eighth notes.
What the bottom number means
The bottom number stands for a note value. Think of it as "one ___ note": a 4 means a quarter note, because it takes four of them to fill a whole note.
| Bottom number | Gets the beat | Examples |
|---|---|---|
| 2 | Half note | 2/2 (cut time), 3/2 |
| 4 | Quarter note | 2/4, 3/4, 4/4, 5/4 |
| 8 | Eighth note | 3/8, 6/8, 7/8, 12/8 |
| 16 | Sixteenth note | 6/16 (rare in band music) |
Most band music uses 4 on the bottom. You'll see 8 on the bottom in marches, jigs and many slow pieces, and 2 in cut-time marches.
Common time signatures in band
4/4 (common time)
Four quarter-note beats per measure. It's the most common time signature, and it's sometimes written as a C instead of numbers. Count 1 & 2 & 3 & 4 & when there are eighth notes.
3/4
Three quarter-note beats per measure: waltzes, many hymns and "Happy Birthday". A dotted half note fills the whole measure.
2/4
Two quarter-note beats per measure. It's common in marches and polkas, and it feels like a quick left-right step.
2/2 (cut time)
Two half-note beats per measure, often written as a C with a line through it. The notes look like 4/4, but you feel two big beats, and quarter notes are only half a beat. See Why cut time feels fast.
6/8
Six eighth notes per measure, felt as two beats of three. The eighth notes are beamed in threes, one group per beat. See Counting 6/8 vs 3/4 for how to count it.
Strong and weak beats
Beats in a measure aren't all equal. Beat 1, the downbeat, is the strongest. It's where the conductor's baton drops straight down. The pattern of strong and weak beats is what gives each time signature its feel.
That's why 2/4 feels like marching, 3/4 feels like swaying, and 4/4 feels steady. When you play, lean slightly into the strong beats and keep the weak ones lighter. Your phrases will sound much more musical.
Simple and compound meter
In a simple meter, each beat divides into two: 2/4, 3/4 and 4/4 are all simple. In a compound meter, each beat divides into three, and the beat is a dotted note.
Here's the shortcut: if the top number is 6, 9 or 12 and the bottom is 8, it's usually compound. Divide the top number by 3 to find how many beats you'll feel. The beat is a dotted quarter note.
| Time signature | Eighth notes per measure | Beats you feel |
|---|---|---|
| 6/8 | 6 | 2 (dotted quarters) |
| 9/8 | 9 | 3 (dotted quarters) |
| 12/8 | 12 | 4 (dotted quarters) |
At very slow tempos your director might conduct 6/8 in six, one beat per eighth note. The groups of three are still there: listen for the accents on 1 and 4.
Odd meters: 5/4 and 7/8
Time signatures with 5 or 7 on top don't split into equal groups. Instead, the beats are grouped in 2s and 3s. A measure of 5/4 is usually felt as 3 + 2 (1 2 3 1 2) or 2 + 3. A measure of 7/8 might be 2 + 2 + 3, 3 + 2 + 2 or another mix.
The beams and the conductor tell you which grouping to use. Eighth notes will be beamed to show the groups, and the conductor's pattern will have a long beat for each group of three. Two well-known pieces in 5/4 are Dave Brubeck's "Take Five" and "Mars" from Holst's The Planets.
Time signature changes
A new time signature can appear in the middle of a piece. It's printed right after a barline and stays in effect until the next one.
- Look ahead. If a change falls at the start of a new line, it's often printed at the end of the line before too, as a warning.
- Watch the conductor. The pattern changes with the time signature, and it's the most reliable way to stay in the right place.
- Mark your part. Circle the change in pencil, or write the new count ("in 3") above the measure.
- Check what stays the same. Some changes keep the beat the same speed, and some keep the eighth note the same. Your director will tell you, and the part may say something like "♩ = ♩".
Practice
Rhythm Trainer and Rhythm Builder both let you pick 4/4, 3/4, 6/8 or cut time. Start with 4/4, then try each of the others. Once they all feel comfortable, choose Random meter so the time signature changes with each rhythm. Before each rhythm plays, check the time signature and say the count-in out loud.
In your band folder, make it a habit: before you play any piece, name the time signature and how many beats you'll feel per measure.