Free Nutrition Calculators

Science-based tools to find your calorie target, daily macros, and protein needs — then turn those numbers into a real meal plan automatically.

Recommended order

1
TDEE Calculator
Find your daily calorie maintenance level
2
Macro Calculator
Split calories into protein, carbs & fat
3
Protein Calculator
Confirm your protein target per meal
4
Meal Planner
Build a week of meals that hit your macros
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TDEE Calculator

How many calories does your body burn every day? Find out in 30 seconds.

  • Mifflin-St Jeor BMR formula
  • 5 activity levels with real-world examples
  • Calorie targets for every goal (loss → bulk)
  • Macro breakdown included in results
  • Meal-matched recipe suggestions
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Macro Calculator

Get exact daily grams of protein, carbs, and fat — personalised to your body weight and goal.

  • Body-weight protein targets (ISSN guidelines)
  • Fat floor for hormonal health
  • 5 goal modes: aggressive loss → muscle gain
  • SVG donut chart macro visualisation
  • Per-meal breakdown (breakfast → snack)
  • Deep-link to meal planner with your macros
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Protein Calculator

Find exactly how much protein you need per day — with per-meal targets and top food sources.

  • Goal-specific targets (0.7–1.1 g/lb)
  • Activity level adjustment
  • Research range bar (min RDA → athlete max)
  • Per-meal protein breakdown
  • 15 high-protein food sources with macros
  • Plant-based combining guidance
3
Free Calculators
5
Goal Modes Each
0
Sign-ups Required
Recalculate Anytime
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Got your numbers? Now build your meal plan.

The Cook This Much Meal Planner takes your calorie and macro targets and builds a full week of recipes that hit them automatically — no manual counting needed.

Build My Meal Plan →

How to Use These Nutrition Calculators

Most people start their nutrition journey with a single question: How many calories should I eat? But calories alone only answer half the question. The three calculators on this page are designed to be used in sequence — each one builds on the output of the previous.

The recommended sequence: TDEE (your calorie budget) → Macros (how to spend that budget) → Protein (your non-negotiable floor) → Meal Planner (execute the plan).

Step 1: TDEE — Your Calorie Starting Point

TDEE (Total Daily Energy Expenditure) is the number of calories you burn on an average day, accounting for your basal metabolic rate and all physical activity. It's calculated using the Mifflin-St Jeor equation — the most validated BMR formula for the general population — adjusted by an activity multiplier. TDEE tells you your maintenance level: eat at this number and your weight stays stable. Eat less to lose fat; eat more to gain muscle.

Step 2: Macros — How to Spend Your Calories

Once you know your TDEE and have adjusted it for your goal (e.g. a 20% deficit for fat loss), the macro calculator splits those calories into protein, carbohydrates, and fat. Unlike tools that use a fixed 40/30/30 split, this calculator anchors protein to your body weight — the approach supported by the International Society of Sports Nutrition — then sets a fat floor to ensure hormonal health, and fills remaining calories with carbohydrates. The result is a macro target that's actually personalised to your physiology, not a generic template.

Step 3: Protein — Your Most Important Number

Protein is singled out in a dedicated calculator because it's the macro that most people consistently under-eat, especially in a calorie deficit. The protein calculator lets you arrive at your daily protein target without calculating TDEE first — useful if you already know your calorie intake and just want to audit your protein. It also provides the research-supported range (minimum to athlete-level) so you can see exactly where your target sits.

Why "Science-Based" Matters

There are hundreds of nutrition calculators online. Most use outdated formulas (Harris-Benedict BMR from 1919), arbitrary macro percentages, or don't distinguish between goals at all. Cook This Much's calculators use the Mifflin-St Jeor equation for BMR (validated in 2005 as the most accurate for non-obese adults), ISSN 2017/2023 position stands for protein targets, and a fat floor derived from endocrine research to protect hormonal function during a deficit. These are the same formulas and guidelines used by registered dietitians and sports nutritionists.

Skip the spreadsheets.

The Meal Planner automatically builds recipes that match your macro targets — nothing to count manually.

Try the Meal Planner →

Frequently Asked Questions

What is a TDEE calculator?
TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in a day across all activity. A TDEE calculator uses your height, weight, age, sex, and activity level to estimate this number using the Mifflin-St Jeor formula. TDEE is the starting point for any nutrition goal: eat at TDEE to maintain, below it to lose fat, above it to gain muscle.
What is a macro calculator?
A macro calculator takes your TDEE and goal and splits your total calories into the three macronutrients: protein, carbohydrates, and fat. Science-based macro calculators anchor protein to body weight (g/lb), set a fat floor for hormonal health, then fill remaining calories with carbohydrates. This produces more precise, goal-appropriate targets than any fixed ratio (like the commonly cited 40/30/30).
Do I need to count macros to lose weight?
You don't need to track macros every day — but knowing your targets is valuable. Most people use a macro calculator once to calibrate their diet, then use structured meal planning to stay on target without daily counting. Cook This Much's meal planner builds weekly meal plans that automatically hit your macro targets, eliminating the need for manual tracking.
How accurate are online nutrition calculators?
Calculators using validated formulas (Mifflin-St Jeor for BMR, ISSN guidelines for protein) are accurate to within 10–15% for most people. Individual variation in metabolism, body composition, and hormonal factors affects actual needs. Treat your result as a well-calibrated starting point, then adjust by 5–10% based on 2–3 weeks of real results.
Which calculator should I use first?
Start with the TDEE Calculator to find your maintenance calorie level. Then use the Macro Calculator to split those calories into protein, carbs, and fat targets based on your goal. Use the Protein Calculator if you only need your protein number — for example, if you're already tracking your diet and just want to verify you're eating enough protein.

Formulas Used

BMR (Males):
10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
BMR (Females):
10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
TDEE: BMR × activity multiplier
Protein: 0.7–1.1 g/lb based on goal (ISSN 2017/2023)
Fat floor: max(0.35 g/lb, 20–25% of calories) ÷ 9

Mifflin-St Jeor (1990). ISSN Position Stand 2017 & 2023.