A transition between two songs sounds much better, if their beats are in sync. This is only possible, if both songs have the same tempo.
In this tutorial, you learn a quick and reliable way to match the tempo of two songs and align their beats properly
If you treat music in your videos as first-class citizens, beat assistant is a tool for you. It automatically detects the beats per minute of your music and assists you in creating animations which are in sync with the music.