A time signature is two numbers at the start of a piece of music that tell you how many beats are in each bar and what note value gets one beat. In 4/4 time, there are four beats per bar, and a quarter note gets one beat, while in 3/4 time, there are three beats per bar, and a quarter note gets one beat.
What is a time signature?
A time signature is two numbers at the start of a piece of music that tell you how many beats are in each bar and what note value gets one beat. The top number tells you how many beats are in each bar, and the bottom number tells you what note value gets one beat: a 4 on the bottom means a quarter note gets one beat, and an 8 on the bottom means an eighth note gets one beat. In 4/4 time, there are four beats per bar, and a quarter note gets one beat, while in 3/4 time, there are three beats per bar, and a quarter note gets one beat, and in 6/8 time, there are six beats per bar, and an eighth note gets one beat. The time signature is the rhythm of the music, and it tells the player how to count the bar, and where the accents fall, and how long the bar is. A piece in 4/4 time has four beats per bar, with the accents on beats one and three, and a piece in 3/4 time has three beats per bar, with the accent on beat one, and a piece in 6/8 time has six eighth-note beats per bar, grouped as two beats of three, with the accents on beats one and four. The metronome keeps the beat, and the G major guitar chord is the chord most players first count with.
How time signatures work
A time signature works by dividing the music into bars, and each bar has the same number of beats, and the beats are the same length, and the player counts them, one, two, three, four, and the bar ends, and the next bar begins. The top number is the count, and the bottom number is the value, and the two together tell the player how to count. In 4/4 time, the count is one, two, three, four, and the value is a quarter note, so each beat is a quarter note long. In 6/8 time, the count is one, two, three, four, five, six, and the value is an eighth note, so each beat is an eighth note long, and the bar is grouped as two beats of three. The time signatures are divided into simple time and compound time. Simple time divides the beat into two, so 4/4 time has four beats, each divided into two eighth notes, and 3/4 time has three beats, each divided into two eighth notes. Compound time divides the beat into three, so 6/8 time has two beats, each divided into three eighth notes, and 12/8 time has four beats, each divided into three eighth notes. The key of C major is the key most pieces are first read in, and the key of G major is the key most songs are first played in.
Worked example — counting in 4/4, 3/4 and 6/8. A piece in 4/4 time has four quarter-note beats per bar, and the count is one, two, three, four, with the accents on one and three, and a bar has four quarter notes, or eight eighth notes, or two half notes. A piece in 3/4 time has three quarter-note beats per bar, and the count is one, two, three, with the accent on one, and a bar has three quarter notes, or six eighth notes, or one dotted half note. A piece in 6/8 time has six eighth-note beats per bar, grouped as two beats of three, and the count is one, two, three, four, five, six, with the accents on one and four, and a bar has six eighth notes, or two dotted quarter notes. The I–V–vi–IV progression in C major can be played in any of the three time signatures, and the count will change with the time.
How to practise time signatures
Practise time signatures by counting out loud, in different times, until the count is a habit and the accents are clear.
- Practise counting in 4/4 time, one, two, three, four, with the accents on one and three, and strumming a G major chord on each beat.
- Practise counting in 3/4 time, one, two, three, with the accent on one, and strumming a C major chord on each beat, feeling the waltz.
- Practise counting in 6/8 time, one, two, three, four, five, six, with the accents on one and four, and strumming a D major chord on each beat.
- Play the I–V–vi–IV progression in C major in 4/4 time, and then in 3/4 time, and notice how the rhythm changes.
- Practise with the metronome set to different time signatures, and count along, until the count is a habit.
Common mistakes
- Confusing the top and bottom numbers — The top number is how many beats are in the bar, and the bottom number is what note value gets one beat, and confusing them will make the count wrong. In 6/8 time, there are six beats, and an eighth note gets one beat, not six quarter notes.
- Counting 6/8 as six separate beats — 6/8 time is grouped as two beats of three, not six separate beats, and counting it as six beats will make the rhythm sound square, not lilting. Count one, two, three, four, five, six, with the accents on one and four, and feel the bar as two beats.
- Ignoring the time signature — A piece must be counted in its time signature, or the rhythm will be wrong, and the accents will be in the wrong place. Check the time signature at the start of the piece, and count in that time, from the first bar.
Quick reference
This table lists the five common time signatures, with the beats per bar, the note value per beat, and the feel for each one, so you can see the time signatures side by side and choose the one that fits the song. The simple time signatures divide the beat into two, and the compound time signatures divide it into three.
| Time signature | Beats per bar | Note value per beat | Feel |
|---|---|---|---|
| 4/4 | Four | Quarter note | Steady, common time |
| 3/4 | Three | Quarter note | Lilting, waltz |
| 2/4 | Two | Quarter note | March-like |
| 6/8 | Six | Eighth note | Lilting, compound |
| 12/8 | Twelve | Eighth note | Rolling, compound |
Use the table as a reference when you read music: find the time signature, check the beats per bar and the note value per beat, and count in that time, from the first bar. When you can count in any time signature without looking, you can play any song, in any time.
Frequently asked questions
What is a time signature?
A time signature is two numbers at the start of a piece of music that tell you how many beats are in each bar and what note value gets one beat. In 4/4 time, there are four beats per bar, and a quarter note gets one beat.
What does the top number of a time signature mean?
The top number tells you how many beats are in each bar: in 4/4 time, there are four beats per bar, and in 3/4 time, there are three beats per bar, and in 6/8 time, there are six beats per bar.
What does the bottom number of a time signature mean?
The bottom number tells you what note value gets one beat: a 4 means a quarter note gets one beat, and an 8 means an eighth note gets one beat, so in 6/8 time, an eighth note gets one beat.
What is the most common time signature?
4/4 time, which is called common time, and it has four quarter-note beats per bar, with the accents on beats one and three. Most pop, rock, and folk songs are in 4/4 time.
What is compound time?
Compound time is a time signature where the beat is divided into three, not two, so 6/8 time has two beats, each divided into three eighth notes, and the feel is lilting and rolling, not square and even.