Methodology

This page explains how each welanutria calculator works, which published method it uses, and where our nutrition data comes from. We believe you should be able to see exactly how a number was produced.

Calories & macros (TDEE)

We estimate your basal metabolic rate (BMR) using the Mifflin-St Jeor equation, widely regarded as one of the most accurate predictive equations for healthy adults. We then multiply by a standard activity factor to estimate total daily energy expenditure (TDEE). Macro splits are calculated from that calorie total using standard energy values (4 kcal per gram of protein and carbohydrate, 9 kcal per gram of fat).

TDEE estimates typically carry a margin of error of around ±10%, because real metabolism varies between individuals. Use the result as a starting point and adjust based on real-world results over a few weeks.

BMI

Body mass index is calculated with the standard formula: weight in kilograms divided by height in metres squared. BMI is a population-level screening tool — it does not distinguish muscle from fat, so it can misclassify very muscular or older individuals. We present it alongside that context.

Ideal weight

We show a healthy weight range for your height, derived from the healthy BMI range (18.5–24.9). We deliberately show a range rather than a single "ideal" number, because no single weight is right for everyone.

Protein

Protein recommendations are based on grams per kilogram of body weight, using ranges supported by sports-nutrition and dietary research, adjusted for activity level and goal. These are general guidelines, not personalised prescriptions.

Water intake

Daily water estimates are based on body weight plus an adjustment for exercise. Individual needs vary with climate, health and diet, so this is a guide rather than a strict target.

Body fat

We estimate body fat using the U.S. Navy circumference method (Hodgdon-Beckett), which uses tape measurements of the neck, waist and (for women) hips, together with height. It is a practical estimate, not a lab measurement; its margin of error is typically around ±3–4 percentage points compared with methods like DEXA.

Nutrition & recipe data

Per-serving nutrition figures come from the USDA FoodData Central database, the U.S. government's authoritative food-composition dataset. Recipes are adapted from public-domain sources, primarily USDA MyPlate Kitchen, and from CC0 (public-domain) recipe collections. Where we calculate nutrition for an adapted recipe, we compute it from the USDA values of each ingredient.

Accuracy & corrections

We check our formulas against authoritative references and aim to keep them correct. If you spot an error, please tell us at hello@welanutria.com and we will review it.

All welanutria tools provide estimates for general information only. They are not a substitute for professional medical or dietary advice.