Biology & Pets

Estimate a dog’s human-age equivalent and life stage using age and size, while understanding why the old seven-year rule is limited.

Use our Hamster Age Calculator to convert hamster years to human years or human age back to hamster age with chart-based interpolation.

Use our Plant Spacing Calculator to estimate how many plants fit in a garden bed, crop row, or square-foot layout from area and spacing.

Use our Bird Age Calculator to convert bird years to human years or human age back to bird age by species or custom lifespan.

Use the Dihybrid Cross Calculator to generate a 4×4 Punnett square, gametes, genotypes, phenotypes, and probabilities for two traits.

Use the Dog Pregnancy Due Date Calculator to estimate a whelping date and delivery window from mating, ovulation, LH surge, or diestrus.

Use our Dog Size & Adult Weight Calculator to estimate your puppy’s adult weight from age and current weight. Quick size prediction with pet category output.

Punnett Square Calculator predicts AA, Aa and aa genotype probabilities and dominant or recessive phenotypes for a simple one-gene genetic cross.

Use this Cat Age Calculator to estimate your cat’s age in human years using the common 15 / 24 / +4 cat age chart. Includes formula, examples, life stages, and care notes.

A safety-first calculator for vet-approved diphenhydramine arithmetic, with checks for dog weight, product ingredients, interactions, and urgent warning signs.