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TDEE Calculator
Your total daily energy expenditure — all calories burned in a day. We run all 4 major BMR formulas at once and show the realistic accuracy range, because no single formula fits everyone.
✦ All 4 BMR formulas + ±15% accuracy range — most show only oneYour stats
Enables Katch-McArdle — more accurate for lean individuals.
Activity & goal
Most people overestimate — when unsure, pick one level lower.
Mifflin-St Jeor is the most widely validated in research.
※ TDEE is an estimate, not a precise measurement. Results vary with genetics, hormones, sleep, and stress. Use as a starting point and adjust from real-world results over 2–3 weeks.
Calorie Deficit Calculator
Find your daily calorie target for fat loss, see your weekly projection, and check whether your chosen rate is safe — including a minimum-threshold warning.
✦ Checks the minimum safe threshold + shows time-to-goalYour stats
Use the TDEE tab to find your number.
Deficit plan
※ 1 kg of body fat ≈ 7,700 kcal. Weekly loss varies with water, glycogen, hormones, and sodium. Track weekly averages, not daily numbers.
Macro Calculator
Calculate your protein, carb, and fat targets. Compare 5 dietary approaches side by side and check whether your protein meets clinical guidelines for your goal.
✦ 5 approaches compared at once + protein adequacy checkYour numbers
Use your TDEE or deficit target.
Checks protein adequacy per kg body weight.
Diet style
The table below shows all 5 approaches at once.
※ No macro split is universally optimal. Research shows adherence is the strongest predictor of outcome — choose an approach you can maintain.
Calorie Surplus Calculator
Find your optimal surplus for muscle gain. Eating too large a surplus stores most of the excess as fat — we show the estimated muscle-to-fat ratio.
✦ Shows estimated muscle vs. fat gain ratioYour stats
Surplus approach
Lean bulking (5–15%) maximizes the muscle-to-fat ratio.
※ Natural max muscle gain: beginners ~1.0–1.5 kg/mo, intermediate ~0.5–1.0, advanced ~0.25–0.5. Progressive training is essential — calories alone won't build muscle.
Weight-Loss Timeline Calculator
Week-by-week projection including metabolic adaptation — as you lose weight your calorie needs fall, slowing loss over time. Most calculators ignore this.
✦ Includes metabolic adaptation — not naive linear mathYour stats
Your plan
Your body burns fewer calories as you lose weight.
※ Real weight fluctuates ±1–2 kg week to week from water, sodium, hormones, and digestion. Track weekly averages over 3–4 weeks. A 2-week plateau is normal.
Learn
Common questions about TDEE & calorie targets
What is TDEE?
Total Daily Energy Expenditure is the total calories your body burns in 24 hours — resting metabolism (BMR), activity, and the thermic effect of food. It's the foundation for any body-composition goal.
Why do calculators differ?
Different formulas (Mifflin-St Jeor, Harris-Benedict, Schofield, Katch-McArdle) use different equations. Individual errors of 300–500+ kcal/day are common — we show all four so you see the range.
How accurate is TDEE?
Studies show calculators land within 100 kcal for only ~20% of people, and ~20% have errors over 500 kcal. Treat your TDEE as a starting estimate and adjust after 2–3 weeks of tracking.
What is a safe deficit?
Around 500 kcal/day supports ~0.5 kg/week loss. Beyond 1,000 kcal/day raises muscle-loss and hormonal risks. Minimum safe intakes are generally 1,200 kcal (women) / 1,500 kcal (men).
Learn
Common questions about calorie deficits & fat loss
What is a calorie deficit?
A deficit means consuming fewer calories than you burn. Your body makes up the difference by drawing on stored energy — primarily body fat — which leads to weight loss over time.
How fast should I lose weight?
Research supports 0.5–1% of body weight per week as a sustainable rate. Faster loss increasingly draws from muscle rather than fat, and raises the risk of fatigue, hormone disruption, and nutrient deficiency.
What's the minimum safe calorie intake?
General guidelines suggest 1,200 kcal/day for women and 1,500 kcal/day for men as a floor. Going below makes it very hard to meet essential nutrient needs and typically accelerates muscle loss.
Why did my weight loss slow down?
As you lose weight, your body adapts by burning fewer calories (metabolic adaptation). Periodic reassessment of your TDEE every 4–6 weeks is normal — reduce intake by 100–200 kcal or add light activity to restart progress.
Learn
Common questions about macros & dietary approaches
What are macros?
Macronutrients — protein, carbohydrates, and fat — are the three main calorie sources. Protein and carbs provide 4 kcal/g; fat provides 9 kcal/g. Tracking them helps control body composition beyond just total calories.
How much protein do I need?
Research consistently shows 1.6–2.2 g of protein per kg of body weight per day supports muscle retention during fat loss and growth during a bulk. Higher intakes (up to 2.4 g/kg) add no harm but show diminishing returns.
Does the carb-to-fat ratio matter?
For most goals, the evidence is weak. Total calories and protein adequacy have far stronger effects on body composition than the carb/fat split. Choose the ratio you can sustain long-term.
Which macro split is best?
There is no universally optimal split. Adherence is the strongest predictor of results. We compare 5 approaches — balanced, high-protein, low-carb, keto, and high-carb — so you can find what fits your lifestyle.
Learn
Common questions about calorie surplus & muscle gain
What is a calorie surplus?
A surplus means consuming more calories than you burn. The excess provides energy for muscle protein synthesis. Without resistance training, most of the surplus goes to fat storage rather than muscle.
How much muscle can I gain naturally?
Rough upper limits: beginners ~1.0–1.5 kg/month, intermediates ~0.5–1.0 kg/month, advanced lifters ~0.25–0.5 kg/month. Actual gains depend on training quality, sleep, protein intake, and genetics.
What is a lean bulk?
A lean bulk targets a small surplus (5–15% above TDEE) to maximize the muscle-to-fat ratio of weight gained. It's slower than a traditional bulk but produces less fat that needs to be cut later.
Should I track protein during a bulk?
Yes. Adequate protein (1.6–2.2 g/kg) is essential — calorie surplus alone does not build muscle. Progressive resistance training creates the stimulus; protein provides the building blocks; the surplus provides the energy.
Learn
Common questions about weight loss timelines & adaptation
What is metabolic adaptation?
As you lose weight, your body adapts by burning fewer calories than a simple weight-based calculation would predict — by up to 5–15%. This is why progress slows beyond what the math says, even with consistent adherence.
Why has my weight loss stalled?
A true plateau (3+ weeks with no movement despite consistent deficit) is a sign that your TDEE has adapted. Common responses: reduce intake by 100–200 kcal, add light exercise, or take a 1–2 week diet break.
What's a healthy rate of weight loss?
Most research supports 0.5–1% of body weight per week as the range that preserves lean muscle while losing mostly fat. Faster rates increase muscle loss, fatigue, and hormonal disruption.
How long will it actually take?
Our timeline uses metabolic adaptation to give a realistic estimate. Most people take 20–40% longer than naive linear math suggests. Building in that buffer prevents discouragement when progress naturally slows.
Privacy Policy
Effective date: 28 June 2026 · Last updated: 28 June 20261. Who we are
BodyMetric.health ("we", "us", "our") operates the website at bodymetric.health — a free collection of health calculators.
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We do not collect, store, or transmit any personal data. All calculations (TDEE, calorie deficit, macros, calorie surplus, and weight-loss timeline) run entirely within your browser. No input values are sent to our servers.
We do not require registration, login, or any form of account creation.
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Disclaimer
Effective date: 28 June 20261. Educational purpose only
All content on BodyMetric.health — including TDEE calculations, calorie targets, macro splits, calorie surplus estimates, and weight-loss timelines — is provided for general educational and informational purposes only. It does not constitute medical, dietetic, nutritional, or clinical advice of any kind.
2. Not a substitute for professional advice
The calculations and information provided by this website are not a substitute for advice from a qualified healthcare professional, registered dietitian, or physician. Always seek professional guidance before making significant changes to your diet, exercise routine, or lifestyle — particularly if you have a medical condition, are pregnant or breastfeeding, or are taking prescription medications.
3. Accuracy of calculations
Our calculators use established, peer-reviewed formulas (Mifflin-St Jeor, Harris-Benedict revised 1984, Schofield/WHO, and Katch-McArdle). However, all calorie and nutrient estimates are approximations derived from population-level research. Individual results may vary significantly due to genetics, hormonal status, medications, medical history, hydration, and body composition. A realistic accuracy range of ±15% is shown on TDEE results for this reason.
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Use of this website does not create a doctor-patient, dietitian-client, nurse-patient, or any other professional relationship. No content on this site should be used for self-diagnosis or self-treatment of any health condition.
5. Special health conditions
People with diabetes, cardiovascular disease, kidney or liver conditions, a history of eating disorders, hormonal disorders, or any other medical condition should consult a qualified healthcare professional before using calculator results to guide dietary or lifestyle decisions.
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