2 x pi x r.
http://wiki.answers.com/Q/What_is_the_formula_for_...

The surface area for a cylinder is S = 2prh + 2pr2 and the circumferance
http://www.chacha.com/question/whatiscircumferen...

Cylinder Formulas. Surface Area = (2 • π • r²) + (2 • π • r • height) Where (2 • π • r²) is the surface area of the "ends&
http://answers.yahoo.com/question/index?qid=200906...

Circumference = 2 * pi * radius (of the circular base)
http://uk.answers.yahoo.com/question/index?qid=200...
