The only time you should be concerned about song length is if it doesn't feel finished to you, or if you're composing for a certain purpose, such as radio or whatever. Songs ranging in length from one minute to ten minutes can be successful if "done well."
In fact, the longer the song, the better it is. Studies have shown that people like listening to songs more than they like reading books. With books, you usually only get through so much material before you have to stop and restart while music keeps going. This isn't necessarily a good thing... but it does show that book readers appreciate lengthier works.
As for music itself, there are two main factors that determine how long it can be: tempo and tone. Tempo means speed; each beat of your heart pumps more blood through your body than a pound of weight. So the faster you breathe, the faster your heart beats, and thus the faster the music plays.
Tone is the quality of sound; some sounds are higher-pitched than others. Violins, pianos, and horns are all high-pitched instruments while drums, bass guitars, and lower voices like baritones and mezzos are low-pitched. As you can see, pitch determines how high or low something will go on a scale.
While the current industry benchmark for popular songs is 3 to 3 1/2 minutes in duration, we've seen a number of terrific and successful songs that are both longer and shorter. There are no one-size-fits-all criteria for song duration since every composer has a unique style, ideas, and aims. However, most songs tend to be around 3 minutes or less because this is enough time to give a listener a chance to get into the music without being bored by its length.
Longer songs are common in many genres including classical, jazz, blues, rock, pop, and experimental. A song may be considered long if it lasts 10 minutes or more. While this does happen from time to time, most songs are too short to be considered an album track.
Short songs are common in folk and country music, where they often serve as introductions to albums or between sets during live performances. A song can be considered short if it lasts 30 seconds or less. These songs are easy to write and perform, which is why you often hear them at open mikes and other amateur performance venues.
It's possible to create songs that are both long and short. Such songs are commonly referred to as "midrange" tracks, which is how they differ from long and short songs. Midrange tracks fall in the middle of the range with respect to length and style, which makes them attractive options for artists looking to include one such song on an album.
Jones is correct. Except for the artist and fans, the duration of a song on an album is unimportant, but a song that expects to generate money and be played on the radio must have a particular length. Either that, or radio stations will cut the music to three to four minutes in length, much like the 45.000-47.500 songs that are played on mainstream rock stations each year.
The typical song length is 3 minutes 20 seconds to 4 minutes 10 seconds. Albums usually contain between 5 and 12 tracks, so there's room for at least one song that falls outside of this range. Some albums may have as few as 4 or as many as 14 songs, but most fall somewhere in the middle, with about 8 to 10 items on them.
In addition to the length of the song, it is also important that listeners know whether or not a song is an outtake, demo, or recording that has no place else on the album. Sometimes these recordings make their way on to future releases, but often they are discarded before being completed. Outtakes can give musicians a chance to try new ideas or change their minds about what they've created, while demos are recordings that musicians make to help find material that fits on an album. Finally, some recordings are only good enough for listening purposes; they aren't finished enough to be released as a single or track on another album. These recordings go directly into a musician's vault.