In genetics, an F2 means a second generation cross, or a cross that is 2 generations away from the original parent breeds. There are 2 ways to get to the second generation. One is to breed an F1 Labradoodle to another F1 Labradoodle, or an F1 Goldendoodle to another F1 Goldendoodle.

The second way is described above, as an F1B. So breeding an F1 Labradoodle or Goldendoodle back to a Poodle to get an F1B, is resulting in a second generation of the hybrid. An F1B Labradoodle puppy or an F1B Goldendoodle puppy is actually a type of F2.