Time signatures explained

Open any piece of sheet music and, right after the clef and the key signature, you will find two small numbers stacked like a fraction. That is the time signature (also called the meter signature). It is one of the first things a performer reads, because it tells you how the music is organized in time before you play a single note.

What do the two numbers in a time signature mean?

The top number says how many beats fit in one measure. A measure (British: bar) is the space between two bar lines. In 3/4 there are three beats in every measure, and in 5/4 there are five.

The bottom number says which kind of note gets one beat. It is a code: 1 means a whole note, 2 means a half note, 4 means a quarter note, 8 means an eighth note, and 16 means a sixteenth note. So 3/4 reads as "three quarter-note beats per measure" and 3/8 reads as "three eighth-note beats per measure."

How do you count a measure?

Say the beat numbers out loud, one number for each beat, starting over at 1 in every measure. In 4/4 you count "1 2 3 4." In 3/4 you count "1 2 3." A half note in 4/4 lasts two counts, and a whole note lasts all four. Count steadily, like a ticking clock, and fit the notes to the count.

Subdivisions go between the beats. Eighth notes fall halfway between two beats, and we say "and" for them: "1 and 2 and 3 and 4 and." The numbers land on the beats and the "ands" land on the off-beats.

Which beats are strong and which are weak?

The beats in a measure are not equally heavy. Beat 1 is the strongest, called the downbeat. In 4/4, beat 3 is the next strongest, and beats 2 and 4 are lighter. This pattern of strong and weak beats is what gives each meter its character, and it is why you can tap your foot to music and feel where the measures begin.

A time signature is therefore more than arithmetic. It tells you how the beats group, and the grouping tells you where the accents belong. When a composer moves an accent onto a weak beat on purpose, we call that syncopation.

What are duple, triple and quadruple meter?

Meters are named by how many main beats are in a measure. Two beats per measure is duple meter, three is triple meter, and four is quadruple meter. March music is usually duple or quadruple, and waltzes are triple.

• Duple: 2/4, 2/2 (cut time), 6/8 (two beats, each divided into three)
• Triple: 3/4, 3/8, 3/2, 9/8 (three beats, each divided into three)
• Quadruple: 4/4, 12/8 (four beats, each divided into three)

Notice that 6/8, 9/8 and 12/8 are named by the number of beats you feel, not by the top number. That brings us to the two big families of meter.

What is the difference between simple and compound meter?

In simple meter each beat divides into two equal parts. In 2/4, 3/4 and 4/4 the beat is a quarter note, and it splits into two eighth notes. In compound meter each beat divides into three equal parts. The beat is a dotted note, because a dotted note is the only simple note value that divides evenly by three.

In 6/8 there are six eighth notes per measure, but you feel them as two beats of three. Each beat is a dotted quarter note, which equals three eighth notes. Likewise 9/8 has three dotted-quarter beats and 12/8 has four. You can read more in the guides to 6/8 and 12/8.

What are some common time signatures?

The most common by far is 4/4, which is why it is also called common time. Then come 3/4 and 2/4. Odd meters such as 5/4 are rarer, but they are easy once you learn to group the beats.

Where does the time signature go, and can it change?

The time signature is written once at the beginning of the first line, after the clef and key signature. It is not repeated on later lines. If the meter changes in the middle of a piece, a new time signature appears at that point, usually after a double bar line. Some pieces change meter often, alternating 3/4 and 2/4 or mixing 5/4 with 4/4.

Two signs replace numbers. A large C stands for 4/4 and is called common time, and a C with a vertical line through it stands for 2/2 and is called cut time.

How do you pick the tempo and feel from the time signature?

The time signature does not tell you how fast to play. That is the job of the tempo marking, such as a metronome number or an Italian word. The signature tells you how to count and where the accents fall. When you start a new piece, read the time signature first, tap or count a measure in your head, and only then add the notes.

1. Look at the top number: how many beats per measure?
2. Look at the bottom number: which note value is one beat?
3. If the top number is 6, 9 or 12 and the bottom is 8, group the eighth notes in threes.
4. Count one measure out loud at a slow tempo before you play.
5. Stress beat 1 slightly, and beat 3 a little in 4/4.

Check yourself

Related pages

• 4/4 time signature
• 3/4 time signature and waltz time
• 6/8 time signature
• Note values: how long each note lasts
• Cut time (2/2)
• Syncopation in music
• Tempo markings: Italian terms and BPM