The Goldendoodle is a crossbreed. Opening your heart and home to a crossbreed is like opening a beautifully wrapped package on your birthday: it's exciting, but you never know what's inside. It’s often assumed that a cross breed will combine the best of two or more breeds, but genetics doesn’t always work that way. The way genes express themselves is not always subject to a breeder’s control, even less so when two different breeds are crossed. That’s something to keep in mind before you lay down lots of money for a dog that you have been assured will be hypoallergenic or healthier than a purebred.
The Goldendoodle is a cross between a Golden Retriever and a Poodle (usually a Standard or Miniature). At their best, they are intelligent, friendly, and affectionate. They come in three sizes: miniature (weighing 15 to 30 pounds), medium (30 to 45 pounds), and standard (45 to more than 100 pounds). Because they are a cross breed, their traits are not fixed, so there is not a guarantee that the Goldendoodle puppy you purchase will fall into the desired weight range. [vetstreet.com]