Time signatures: what the two numbers mean
A time signature is the pair of numbers at the start of a piece. In simple meters, the top number says how many beats are in each bar, and the bottom number says which note gets the beat. Compound meters like 6/8 work a little differently, but don't worry, we'll get there step by step. In this guide, you'll learn how to read and count each of them, and you'll hear every one.
Simple meters: 2/4, 3/4, 4/4
Let's start with the most familiar. In 4/4, there are four beats per bar, and the quarter note, shown by the 4 at the bottom, gets the beat. It's so common that it's called common time, and it's often written as a C. 3/4 has three quarter-note beats, which gives the feel of a waltz. 2/4 has two, the feel of a march. In each of them, the beat divides into two eighth notes.
- Meter
- 4/4: simple meter
- Beats per measure
- 4 beats
- Beat unit
- quarter note
- Beat division
- duple: 2 eighth notes per beat
- Reading the numbers
- 4 = number of beats; 4 = the quarter note, which gets one beat
- Corresponding meter
- 12/8 (compound: top ×3, bottom ×2)
- Strong beats
- beat 1 strong, beat 3 strong for Danhauser (medium in current usage), beats 2 and 4 weak
Compound meters: 6/8, 9/8, 12/8
Now for compound meter, so let's take our time. In 6/8, the bar holds six eighth notes, but you feel two beats, each one a dotted quarter divided into three. That lilting one-two-three, four-five-six is the signature of compound meter. 9/8 has three of these beats, and 12/8 has four. Here is the rule: if the top number is 6, 9 or 12, divide it by three to get the number of beats.
- Meter
- 6/8: compound meter
- Beats per measure
- 2 beats
- Beat unit
- dotted quarter note
- Beat division
- triple: 3 eighth notes per beat
- Reading the numbers
- 6 = number of beat-thirds; 8 = the eighth note, one third of a beat
- Corresponding meter
- 2/4 (simple: top ÷3, bottom ÷2)
- Strong beats
- beat 1 strong, beat 2 weak
Cut time and other signatures
- 2/2, or cut time, written ¢, has two half-note beats per bar. You'll often find it in marches and fast music.
- 5/4 has five beats, usually felt as three plus two, or two plus three. “Take Five”, written by Paul Desmond for the Dave Brubeck Quartet, is the classic example.
- 7/8 and 7/4 have seven, grouped as two plus two plus three, or something similar. Pink Floyd's “Money” is mostly in 7/4.
Italian tempo terms do not give an exact speed: these ranges are rough guides that vary by period and edition. M.M. = Maelzel's metronome (1815).