How to Calculate the Time Signature of a Song

Sometimes, in order to play and/or appreciate a song, you need to know the time signature of the song. Some are easy to figure out, such as common signatures like 4/4 or 3/4. However, some are quite difficult to figure out. This guide should help you.


1. Learn the meaning of time signatures. A time signature represents the length of the melody in a song. There are common signatures, such as quadruple (4/4) and triple (3/4) time. Most songs are written in this time. However, some songs are written in uncommon time signatures, such as 5/4, 7/4, and 9/4. Time signatures look like fractions. The top number represents how many beats there are in a measure, and the bottom number represents the note value which makes one beat.

2. Listen to the song. First you must listen to the song fully. Although almost all songs stay the same time signature for the whole song, in some instances songs use two time signatures like one for the verses and a different one for the chorus, and in rarer cases have multiple time signatures throughout (see Prokofiev and Shostakovich symphony scores).

3. Get a feel for the melody. The melody of a song is the thing you listen to overall in a song. The melody in a song usually repeats, and is the best way to calculate the time signature of a song. You need to get a feel for when it ends or starts. If the melody is not present, you may want to listen to the rhythms in the drums or such instruments. If the melody is present and keeps repeating, you can start.

4. Find out the "Top Number". An easy strategy to do this is counting on your fingers. When the melody or rhythm starts, start counting. Every beat, add a finger until the melody starts over, which is when you start at one again. Chances are, the number is 4 or 8, the most commonly used time signature. Whatever number is the one you end up with before it starts over is the top number on the fraction of the time signature. Be aware that many songs have a "Pick-up Note", so it may be more efficient if you base of the accentuated notes, not the beginning note.

5. Find out the "Bottom Number". For this, you must find out if the melody is faster than the actual song. A song's time signature's bottom number is almost always 4 or 8. Listen to the bass (or left hand); is the melody twice as fast? Is the melody in 8th notes or 4th notes? If you think it could be twice as fast or in 8th notes, the bottom number is probably 8. If it seems it is in 4th notes, the bottom number is probably 4.

Tags: How To, Music