A time signature tells you how many beats are in each measure and which note value gets one beat. It appears at the beginning of a piece, right after the clef and key signature, and looks like a fraction — but it works differently from mathematical fractions.
The top number tells you how many beats are in each measure. The bottom number tells you which note value represents one beat: 4 = quarter note, 8 = eighth note, 2 = half note. So 4/4 means four quarter-note beats per measure. 6/8 means six eighth-note beats per measure.
When the top number is 6, 9 or 12, each beat is subdivided into three equal parts rather than two. 6/8 has two dotted-quarter-note beats, each divided into three eighth notes — giving a "ONE-two-three FOUR-five-six" feel. 9/8 has three beats ("slip jig" feel). 12/8 has four beats (slow blues feel).
Many pieces change meter mid-stream — a new time signature appears at the beginning of a measure where the change occurs. This is common in musical theatre, film scores, and progressive music. When practicing, count carefully through meter changes and use a metronome to keep the underlying pulse steady.
Download our time signature practice worksheets and use our blank staff paper to write your own exercises in different meters.