What Does F1, F1b, F2 and F3 Mean in Dog Breeds?

By: Matt

The classifications F1, F2, and F3 describe how far ‘designer breeds’/Crosses such as Poodle mixes are from the original purebred mating.

The ‘F’ stands for Filial (Genetics. pertaining to the sequence of generations following the parental generation) and the number represents what mating it is starting from the original purebred pairing e.g. an F1 Labradoodle is the result of a Labrador and a Poodle mating. An F2 Labradoodle is the result of two Labradoodles mating.

The letters and numbers may seem confusing when looking at dogs but this article, with the use of Poodle mix examples, will help you fully understand the breeding code, discover what a ‘b’ means when included, and find out if there are any issues with these cross-bred dogs.

Understanding Designer Breeds

Before we discuss Poodle mixes further, it’s important to understand what a designer breed is. In the U.S., the AKC recognizes 200 breeds of designer dogs, and dogs who belong to these breeds are purebred.

A growing number of breeders are creating designer breeds by mixing two purebred animals. The purpose of these mixes is to obtain pets with characteristics that make two different breeds lovable, but some breeders also create designer breeds to improve the health of the offspring.

Poodles are popular because they have few health risks compared to other breeds. Hip dysplasia, heart problems, epilepsy, and other health issues are far less common in Poodles.

Plus, Poodles have a dense coat of curled hair that their offspring often inherits. This hair type makes puppies look like miniature teddy bears, which helps explain why these designer breeds are so popular.

It’s also worth noting that Poodles shed less than other dogs, which makes Poodle mixes ideal for those with allergies.

Prospective pet owners looking into designer breeds will quickly notice that many of these popular mixes involve Poodle:

  • Labradoodles are a mix between a Poodle and a Labrador Retriever.
  • Goldendoodles are the result of breeding a Poodle with a Golden Retriever.
  • Some breeders specialize in Cockapoos, which are mixes between a Poodle and a Cocker Spaniel.
  • You can also find Terripoos, a mix between a Terrier and a Poodle.

What Is an F1 Dog?

When describing designer breeds, the letter F stands for filial. The number that follows reflects the level of filiation to the original purebred dogs.

An F1 Poodle mix results from breeding two purebred animals. One of the parents is a purebred Poodle, while the other can be a purebred Golden Retriever, Cocker Spaniel, or other breeds.

An F1 puppy will have 50% of its genetic material from a purebred or P dog.

F1 Poodle mixes tend to cost more, but these dogs are more likely to display the traits that make the designer breed popular, especially regarding their physical appearance.

What Is an F1b Dog?

An F1b Poodle mix is the offspring of an F1 dog and a purebred animal. You can find F1b Poodle mixes with a purebred Poodle parent, but some breeders produce puppies with a purebred parent from another breed.

The result is a dog with 75% of Poodle DNA and 25% from another breed if the breeder uses a purebred Poodle parent.

When creating a designer breed, breeders often seek to isolate traits from the two breeds they are crossing. F1b mixes help reinforce the desired traits of a specific breed.

For instance, an F1b Poodle mix with a purebred Poodle parent has a stronger probability of having curly hair that doesn’t shed.

Some breeders also offer F1bb mixes. An F1bb Poodle mix results from breeding a purebred dog with an F1b mix. If both generations have a purebred Poodle parent, 12.5% of the F1bb offspring’s DNA will come from another breed.

What Is an F2 Dog?

The number that follows the letter F refers to the generation. For instance, an F1 Poodle mix is a first-generation Labradoodle or Goldendoodle.

The F2 code indicates the dog is a second-generation designer breed, and these dogs result from breeding two F1 parents.

The DNA proportions are the same as an F1 dog. Since each parent has 50% of DNA from the two original breeds, their offspring will have 50% of Poodle DNA and 50% of Golden Retriever, Cocker Spaniel, or Labrador Retriever DNA.

However, an F2 Poodle mix has genetic material from a wider pool since the breed-specific DNA comes from four purebred grandparents.

By breeding similar dogs together for centuries, humans have created gene bottlenecks and reduced the diversity that naturally exists in the canine species. This phenomenon explains why many purebred dogs are at risk of developing health issues.

F2 mixes are a great way to diversify a dog’s lineage and produce healthier puppies.

Some breeders go further by backcrossing a dog’s lineage and breeding an F2 dog with a purebred parent. The result is an F2b puppy. An F2b dog will have a diverse lineage but her breed-specific traits might be stronger thanks to the purebred parent.

What Is an F3 Dog?

Breeders create F3 Poodle mixes by breeding two F2 parents together. The F3 offspring still possesses 50% of Poodle DNA and 50% from another breed, but their genetic makeup is much more diverse since their genetic material comes from a total of eight purebred great-grandparents.

Few breeders will go further, but it’s technically possible to create an F3b Poodle mix by having an F3 dog mate with a purebred Poodle or to breed two F3 individuals together to create an F4 generation.


Are There Any Issues With These Poodle Mixes?

Before adopting a pet, you should compare the pros and cons of different Poodle mixes. Here’s what you should know about potential issues with the different levels of parentage that exist.

F1 Poodle Mixes

An F1 mix will retain the distinct genetic characteristics of the two purebred parents. Unfortunately, these dogs are also more likely to inherit the less desirable traits of these two breeds.

The good news is that the Poodle parent isn’t likely to pass on genetic material that increases the offspring’s risk of developing a serious health condition. Poodle hair genes are also dominant, so an F1 puppy will likely have the hypoallergenic coat that makes Poodles popular.

However, a Labrador Retriever or Golden Retriever parent can pass on genes that increase the risks of hip dysplasia since these breeds are at risk for this condition. A Cocker Spaniel parent can transmit genetic materials that make the offspring prone to developing ear and skin infections or cherry eyes.

On the plus side, the parentage of an F1 puppy is usually easy to track, and the breeder should have paperwork for the two purebred parents. You can also pick a responsible breeder who will have the parents screened for risks of hip dysplasia and other conditions.

F1b Poodle Mixes

An F1b mix should have a lower risk of developing health issues associated with Labrador Retrievers, Golden Retrievers, and other breeds.

However, your F1b puppy will have an appearance closer to a Poodle than an F1 mix. The two purebred Poodle ancestors can also pass on undesirable genetic traits, such as an increased risk of heart disease if the breeder is working with miniature Poodles.

F2 and F2b Poodle Mixes

With F2 and F2b Poodle mixes, a breeder is using a wider genetic pool and should be able to reduce the offspring’s risk of developing health issues.

However, issues can arise if you purchase an F2 or F2b puppy from an unscrupulous breeder who practices inbreeding.

In theory, an F2 dog should have four unique purebred grandparents, while an F2b puppy should have an F2 parent and a purebred parent. Untrustworthy breeders might reuse the same purebred dogs at different stages of this process.

For instance, an F2b puppy could have a purebred parent that is also their grandparent. An F2 puppy can be the result of breeding two half-siblings. You must also watch out for F2b breeders using purebred parents without screening these dogs first.

If you’re in the market for an F2 or F2b Poodle mix, choose a reputable breeder and ask about the dog’s family tree.

F3 Poodle Mixes

An F3 Poodle mix should be healthier since there is a larger genetic pool. However, these dogs can be challenging to find since few individuals will breed Goldendoodles, Labradoodles, and other designer breeds for more than two generations.

The dog’s parentage can also be difficult to trace over three generations, and there is a potential risk of inbreeding if you’re purchasing an F3 mix from a low-quality breeder. Some individuals will reuse purebred dogs if they have a limited pool since adding dogs to their breeding pool results in increased costs.

You might also end up with a puppy who has an ancestor that isn’t a purebred dog since keeping track of the lineage over three generations isn’t easy.


Designer breeds are an excellent fit for pet owners who want a pet with reduced risks of developing severe health problems. However, selecting a reputable breeder who can provide clear information about your new puppy’s family tree is crucial to determine any known issues with the breed. 

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Enthusiastic Poochon/Bichpoo/Bichonpoo (how many names) Owner. Husband, Father and Dog walker extraordinaire.

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