Tonight I wanted to write a quick guide how to figure out how AN hoses and fittings are sized. You’ve probably seen things like “-6 AN hose” and wondered what does that mean?

Well figuring out AN sizes is fairly simple. The AN size number such as -4 AN or -6 AN, etc. relates to 1/16 of an inch, and is measured on fittings and hoses from the I.D. (inside diameter).

Here is a quick reference guide to figure out common AN sizes:

  • -2 AN = 1/8 inch (0.125″)
  • -3 AN = 3/16 inch (0.1875″)
  • -4 AN = 1/4 inch (0.25″)
  • -5 AN = 5/16 inch (0.3125″)
  • -6 AN = 3/8 inch (0.375″)
  • -7 AN = 7/16 inch (0.4375″)
  • -8 AN = 1/2 inch (0.50″)
  • -9 AN = 9/16 inch (0.5625″)
  • -10 AN = 5/8 inch (0.625″)
  • -11 AN = 11/16 inch (0.6875″)
  • -12 AN = 3/4 inch (0.75″)
  • -14 AN = 7/8 inch (0.875″)
  • -16 AN = 1 inch (1.00″)
  • -18 AN = 1-1/8 inch (1.125″)
  • -20 AN = 1-1/4 inch (1.25″)

So to sum it up, simply take the AN number such as -6 AN, and turn it into a fraction of 1/16. In this case -6 AN = 6/16 = 3/8 inch. Basically a -6 AN hose is the same as a 3/8 inch hose.