Free calculators for fitness, health, nutrition & everyday life.
Everfitly is a collection of free, easy-to-use calculators covering fitness, body composition, nutrition, pregnancy, and general health screening. No signup, no paywall — just a number field, a Calculate button, and a clear result.
Most people don't need a fitness app with a login and a subscription just to check their BMI or figure out how much protein they should be eating. We wanted a place where you could get a straight answer in a few seconds, understand what it means, and move on with your day.
Every calculator on this site is built on established, published formulas and reference data — not guesswork. Where a widely used standard exists (like the CDC growth charts, WHO healthy weight ranges, or the CKD-EPI kidney function equation), we use it directly rather than approximating it.
That said, every result on this site is an estimate based on general formulas. Estimates are a helpful starting point, but they don't replace a conversation with a doctor, dietitian, or qualified trainer who knows your actual health history.
Found something that doesn't look right, or have a calculator you'd like to see added? Visit our Contact page — we'd like to hear from you.