Octave (Musical interval)

An octave is like a note’s “big brother” or “little brother”! 

It’s the same note, but it sounds either higher or lower.

For example, if you play the open E string on your guitar and then play the 12th fret on the same string, that’s an octave—both are E, but the one at the 12th fret is higher.

Here’s a cool way to think about it: an octave happens when one note vibrates exactly twice as fast (or half as fast) as another.

This makes them sound similar, even though one is deeper or brighter.

On the guitar, you can find octaves in lots of places.

A common trick is this: if you play a note on one string, its octave is often two strings down and two frets over. For example, a note on the 3rd fret of the low E string has its octave on the 5th fret of the D string.

Why does this matter? Octaves are everywhere in music. They help you play melodies, understand and memorize the fretboard, and make your music sound richer. Plus, they’re fun to find and play!

Think of octaves as the same note in different “voices.” 

Also good to remember:

An octave is the distance between a note and the next time it appears in the musical scale, spanning 8 notes and 6 full tones.