Dog Age Calculator
The old "multiply by 7" rule is inaccurate — dogs mature rapidly in year one, then age at a rate that depends heavily on size. This calculator uses a more realistic, non-linear scale.
Why size changes the math
Larger dogs mature faster in early life but also age faster once past adolescence, which is why a giant breed's average lifespan (often 7-10 years) is notably shorter than a small breed's (frequently 14-16 years). This calculator applies a size-adjusted rate after age two rather than a flat multiplier, which is a closer approximation of how veterinarians actually think about canine aging.
What this doesn't capture
Individual health, genetics, and breed-specific conditions all affect biological aging independent of this formula. Use this as a general reference point for understanding your dog's life stage, not a precise medical metric.