I get many questions on figure classes and size. While I am not going to pull out a ruler and measure every figure I will give users out there an idea of what to expect.
About 1.5 times the size of a hot wheels
Twice as big as a legends class
The most common size what you see the most on store shelves, about 4" long in vehicle mode typically
1.5 times the size of deluxe class
Little bigger than voyager but usually with more bells and whistles like sound and lights
Your typical leader figure, usually Optimus and Megatron. About 1 foot high.
Oversized monster figures rarely surpassed, examples Unicron, and Primus
Only one figure to date. Ultimate Bumblebee. Do not count the updated version as a second figure.