Body & Diet Calculators
These calculators translate a few measurements into the numbers that guide health and nutrition decisions: how your weight compares, how much energy you burn, and how much of each nutrient to aim for. Each uses an established, published formula.
They build on one another. Your BMR (calories burned at rest) feeds your calorie target, which in turn sets your protein and fat ranges — while BMI, body fat and ideal weight describe where you are now. Reading them together gives a fuller picture than any single number.
None of these is a diagnosis. They are screening and planning estimates — useful starting points to discuss with a healthcare professional, not substitutes for one.
Which calculator should I use?
- BMI Calculator A quick weight-to-height screen and your healthy weight range. Open calculator →
- BMR Calculator Calories your body burns at complete rest. Open calculator →
- Calorie Calculator Daily calories to maintain, lose or gain weight. Open calculator →
- Body Fat Calculator Estimate body fat percentage with a tape measure. Open calculator →
- Ideal Weight Calculator A healthy target-weight range from four formulas. Open calculator →
- Protein Calculator Daily protein target for your weight and goal. Open calculator →
- Fat Intake Calculator Daily fat range within your calorie target. Open calculator →
Reference tables
At-a-glance tables you can cite, print or embed — computed from the same formulas as the calculators.
- BMI chart The healthy, overweight and obese weight ranges for each height, based on the WHO BMI thresholds (18.5, 25 and 30) — in pounds and kilograms. View the table →
- Ideal weight chart Ideal body weight for each height, for men and women, as a range across the Robinson, Miller, Devine and Hamwi formulas. View the table →
Guides on this topic
- BMI, BMR and Calories, Explained What BMI, BMR and TDEE actually mean, how they relate to each other, and how to use them together to set realistic, healthy goals — with calculators built in.
- The Complete Guide to Healthy Weight How BMI, body fat, BMR and calories fit together — a practical, no-fads framework for reaching and maintaining a healthy weight, backed by the numbers.
- What's a Healthy Weight for Your Height? Ideal-weight formulas, what they really tell you, and why a healthy weight is a range — not a single number on the scale.
- Body Fat Percentage: What's Healthy? Why body fat percentage beats the scale, what a healthy range looks like for men and women, how to measure it at home, and how to lower it sustainably.
- How Much Protein Do You Really Need? Daily protein targets for everyone from desk workers to lifters, why protein matters, and how to hit your number with everyday foods.