What is the exact mm of uv filter lens for my nikon D5100 with 18-55 lens?

What is the exact mm of uv filter lens for my nikon D5100 with 18-55 lens?

Added (1). Thanks for the answers… You both right. Now i can order it online.

52 mm… That information is on the lens

Or can be found here for any of the Nikkor lenses

http://www.nikonusa.com/...index.page

Look on the back of the lenscap. You'll see something like LC-52 or LC-58 that's the threadsize for your filters for that lens. It may also be written Ø52 or Ø58 if the cap is Brand-X.