F1 –An F1 Doodle is a first-generation cross between a Poodle and another purebred dog parent. This makes the genetic makeup of an F1 Doodle 50% Poodle and 50% of the other original breed parent.
F1b – An F1b Doodle is a first-generation backcross between an F1 Doodle and a Poodle. The genetic makeup of an F1b Doodle is therefore 75% Poodle and 25% of the other original breed parent.
Sometimes the other original purebred parent is used instead of the Poodle.
F2 – An F2 Doodle, or second-generation Doodle, has two F1 Doodle parents. Like the F1 Doodle, F2 Doodles have a close to 50-50 mix of the Poodle and the other original purebred parent.
F2b - An F2b Doodle is a second-generation backcross Doodle. Similarly, to F1b Doodles, F2b Doodles have an F2 Doodle parent and a Poodle parent. Their genetic makeup consists of 75% Poodle and 25% of the other purebred parent. Likewise, sometimes the other original breed parent is used in the backcross instead of the Poodle
Multigeneration – A cross between doodles from varying generations. The genetic breakdown will vary depending on the cross used.