Intervals: Guitar's Secret Decoder Ring

This was the 9th Fret Science YouTube video, released on July 16, 2023. As of December 2025, it has been viewed 378k times, making it my third-most-watched video.

Original video description: Intervals are the building blocks of music, and the guitar fretboard makes them easier to identify and visualize than any other instrument. Learn a simple counting trick that will enable you to identify any interval on the fretboard and then use it to demystify any chord voicing.