Why measure a form at all
Because the length is the thing you have to hold on to. A soloist who loses count is not lost in the harmony, which repeats; they are lost in the FORM, which is longer than the harmony and turns over less often. Knowing that one shape runs twelve bars and another thirty-two is the difference between playing three choruses and playing until somebody looks at you.
Counted, not asserted
Every figure above comes out of the declared bars. The section count is the number of declared sections; the bar count is their lengths added up; the chorus length is the section order expanded and summed, which is why a form written as sixteen bars reports thirty-two. Nothing on this page is a number somebody remembered.
One form deliberately reports no chorus length at all. The turnarounds are declared as alternatives rather than as a sequence — a group picks one — and a set of choices has no length, so the engine refuses to invent one rather than adding them up and producing a figure nobody could play.
Bars that hold two chords
The other column worth reading is how many bars carry more than one chord. That is harmonic rhythm, and it is what makes a pair of forms of the same length feel completely different: a blues spends most of its bars on a single chord, while a turnaround puts four chords into two bars and never sits still. A rhythm section reads that column before it reads the chords.
Why there is no list of tunes
The melodies are somebody's copyright and are not this site's to publish. The shapes underneath them are not — they are the common property of everybody who has ever played this music, and they are also the part that transfers. Learn a shape and you have learned the frame under a great many tunes at once; learn a tune and you have learned one tune.