So what is the average length of a song these days? The average length of a popular song, according to the most recent Billboard Hot 100, is about 3 minutes and 30 seconds. Hit songs are about 3 minutes long because of two major factors: the historic popularity of the 45 rpm record and the monetization methods applied by radio stations and record producers throughout the 20th century. Here I’ll discuss some of my all-time favorite lengthy tunes.