Puppy Weight Calculator

This tool estimates a puppy's grown weight from its age in weeks, its weight today and the size group its breed finishes in. Each size group carries a percent-of-adult-weight curve pinned to the published rules of thumb, a quarter of adult weight at 6 weeks and half at 12 weeks for small breeds, 40 percent at 14 weeks for medium, half at 20 weeks for large and half at 24 weeks for giant, with straight-line interpolation between those ages. A second option ignores the curve and simply takes the midpoint of the sire and dam's grown weights, which is often the better guide for a purebred litter. Individual dogs vary widely and litter mates can finish pounds apart, so the answer comes with a deliberately loose range and a weigh-in at six months is worth far more than one at eight weeks.