Nutrition calculators

51 live nutrition calculators inside Health & Medical on The Online Calculator 24. Every engine shows its formula, the worked steps behind the default figures, and the standard or dataset the method comes from.

Live Nutrition tools

• Calorie Needs Calculator — Estimate your daily calorie needs (TDEE) for maintenance, weight loss or muscle gain, based on Mifflin-St Jeor BMR and your activity level.
• BMR (Mifflin-St Jeor) Calculator — Estimate your basal metabolic rate — the calories your body burns at complete rest — using the Mifflin-St Jeor equation, the accuracy standard.
• BMR (Harris-Benedict) Calculator — The calorie floor and ceiling for bmr (harris-benedict): resting burn plus lifestyle, from the Mifflin-St Jeor equation — the one dietetic bodies still endorse.
• BMR (Katch-McArdle) Calculator — The plain odds behind bmr (katch-mcardle): single-event probability, the fair-price payout it implies, and how repetition moves the chance of at least one success.
• BMR (Schofield) Calculator — The calorie floor and ceiling for bmr (schofield): resting burn plus lifestyle, from the Mifflin-St Jeor equation — the one dietetic bodies still endorse.
• Advanced TDEE & Macro Nutrition Calculator — Scientific Total Daily Energy Expenditure (TDEE) calculator powered by Katch-McArdle and Mifflin-St Jeor formulas, with custom macro splits, lean mass tracking, and carb cycling.
• Calorie Deficit Calculator — Turn a weight-loss goal into a daily calorie target and a realistic date — with safe-rate guardrails built in.
• Calorie Surplus Calculator — The calendar answer behind calorie surplus: at your chosen daily balance, the pounds move on this date — using the 7,700-kcal-per-kg energy equivalent.
• Weight Loss Rate Calculator — The calendar answer behind weight loss rate: at your chosen daily balance, the pounds move on this date — using the 7,700-kcal-per-kg energy equivalent.
• Weight Gain Rate Calculator — The calendar answer behind weight gain rate: at your chosen daily balance, the pounds move on this date — using the 7,700-kcal-per-kg energy equivalent.
• Protein Needs Calculator — Get an evidence-based daily protein target for your weight, activity and goal — in grams, plus per-meal guidance.
• Protein per Pound Calculator — A transparent linear conversion for protein per pound: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Protein per kg Calculator — A transparent linear conversion for protein per kg: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Carbohydrate Needs Calculator — A transparent linear conversion for carbohydrate needs: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Fat Needs Calculator — A transparent linear conversion for fat needs: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Fiber Needs Calculator — A transparent linear conversion for fiber needs: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Water Needs Calculator — Estimate your daily water requirement from body weight, activity and climate — in cups, liters and ounces.
• Sodium Limit Calculator — A transparent linear conversion for sodium limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Potassium Target Calculator — A transparent linear conversion for potassium target: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Calcium Needs Calculator — A transparent linear conversion for calcium needs: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Iron Needs Calculator — A transparent linear conversion for iron needs: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Vitamin D Dose Calculator — A transparent linear conversion for vitamin d dose: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Omega-3 Needs Calculator — A transparent linear conversion for omega-3 needs: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Saturated Fat Limit Calculator — A transparent linear conversion for saturated fat limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Trans Fat Limit Calculator — A transparent linear conversion for trans fat limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Cholesterol Limit Calculator — A transparent linear conversion for cholesterol limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Sugar Limit Calculator — A transparent linear conversion for sugar limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Added Sugar Limit Calculator — A transparent linear conversion for added sugar limit: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Alcohol Calories Calculator — A transparent linear conversion for alcohol calories: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Alcohol Units Calculator — A transparent linear conversion for alcohol units: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Net Carbs Calculator — A transparent linear conversion for net carbs: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Glycemic Load Calculator — The glycemic load payment, total interest and true cost of borrowing for any principal, APR and term — the same amortisation maths every lender’s disclosure uses.
• Glycemic Index Impact Calculator — The glycemic index impact payment, total interest and true cost of borrowing for any principal, APR and term — the same amortisation maths every lender’s disclosure uses.
• Insulin Load Calculator — A transparent linear conversion for insulin load: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• PRAL Score Calculator — Attainment of pral score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• ORAC Score Calculator — Attainment of orac score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• Nutrient Density Calculator — A transparent linear conversion for nutrient density: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Caloric Density Calculator — A transparent linear conversion for caloric density: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Food Score Calculator — Attainment of food score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• Diet Quality Index Calculator — The plain odds behind diet quality index: single-event probability, the fair-price payout it implies, and how repetition moves the chance of at least one success.
• Mediterranean Diet Score Calculator — The plain odds behind mediterranean diet score: single-event probability, the fair-price payout it implies, and how repetition moves the chance of at least one success.
• DASH Score Calculator — Attainment of dash score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• MIND Diet Score Calculator — The plain odds behind mind diet score: single-event probability, the fair-price payout it implies, and how repetition moves the chance of at least one success.
• Flexitarian Score Calculator — Attainment of flexitarian score against a target, with the absolute gap and the weighted contribution for scorecard roll-ups.
• Vegan Protein Completeness Calculator — A transparent linear conversion for vegan protein completeness: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Vegetarian Iron Absorption Calculator — A transparent linear conversion for vegetarian iron absorption: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Calcium Absorption Rate Calculator — A transparent linear conversion for calcium absorption rate: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Vitamin B12 for Vegans Calculator — A transparent linear conversion for vitamin b12 for vegans: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Intermittent Fasting Window Calculator — Turns a fasting protocol (16:8, 18:6, 20:4 OMAD or 14:10) and your first meal time into an exact eating window, the moment your fast breaks each day, and a printable daily schedule.
• Ramadan Fasting Calorie Calculator — A transparent linear conversion for ramadan fasting calorie: the factor is visible, the arithmetic is shown, and the inverse direction comes free.
• Alternate Day Fasting Calculator — A transparent linear conversion for alternate day fasting: the factor is visible, the arithmetic is shown, and the inverse direction comes free.

Reading a Nutrition result

A number on its own is the weakest thing a calculator can give you, so these tools pair each output with the comparison that gives it meaning: the gap to a target, the band the value falls in, or what a realistic swing in one input does to the answer. When a figure looks wrong, that is usually the fastest place to check — re-run it with one input moved and see whether the change lines up with the formula printed above the result.

Related sub-topics in Health & Medical

• Body Measurements — 51 live tools.
• Fitness Performance — 54 live tools.
• Clinical Calculators — 53 live tools.
• Medications & Dosing — 50 live tools.