Calorie Calculator | TDEE & Weight Goals
Calculate daily calories using Mifflin-St Jeor, Harris-Benedict, or Katch-McArdle. Find your TDEE and set calorie targets for weight loss, maintenance, or muscle gain.
Sex
Units
BMR Formula
Goal
Press Enter to calculate · Esc to reset
What Is the Calorie Calculator | TDEE & Weight Goals?
Your body burns calories every minute, even while asleep. TDEE (Total Daily Energy Expenditure) is the total calories your body uses in a day, combining your resting metabolism with the energy cost of physical activity. Matching your calorie intake to your TDEE keeps weight stable; eating less creates a deficit; eating more creates a surplus.
BMR (Basal Metabolic Rate) is the foundation, the calories your body needs just to keep vital functions running at complete rest. It accounts for 60–75% of TDEE in sedentary people. All three formulas estimate BMR from measurable inputs, but they were developed on different populations and have different strengths.
The activity multiplier accounts for all non-resting calorie burn, exercise, non-exercise activity thermogenesis (NEAT), and the thermic effect of food. Most people underestimate their activity level; use your realistic weekly average, not your best day.
Formula
Step 1, Basal Metabolic Rate (BMR)
Mifflin-St Jeor (recommended for most people):
Harris-Benedict Revised (1984):
Katch-McArdle (requires body fat %):
Step 2, Total Daily Energy Expenditure (TDEE)
Activity factors:
| Level | Multiplier | Who It Fits |
|---|---|---|
| Sedentary | ×1.20 | Office work, no structured exercise, few steps per day |
| Lightly Active | ×1.375 | Light cardio or weights 1–3×/week, mostly desk job |
| Moderately Active | ×1.55 | Gym or sport 3–5×/week, mixed desk and standing job |
| Very Active | ×1.725 | Hard training 6–7×/week or physical job plus exercise |
| Extra Active | ×1.90 | Manual labour all day plus regular intense training |
Step 3, Goal Calorie Targets
W = weight kg · H = height cm · BF% = body fat percentage · LBM = lean body mass
How to Use
- 1Choose units: Select Metric (kg / cm) or Imperial (lbs / ft + in), the inputs will update accordingly.
- 2Enter your details: Fill in sex, age, weight, and height. Use a preset to quick-fill a common profile.
- 3Pick an activity level: Click the button that best matches your realistic weekly average, not your best or worst day.
- 4Select a BMR formula: Mifflin-St Jeor works for most people. Choose Katch-McArdle if you know your body fat % from a DEXA scan or navy method measurement.
- 5Choose a goal: Select Lose Fast, Lose Weight, Maintain, Lean Gain, or Bulk. The goal pre-selects a calorie target and protein range.
- 6Calculate: Press Enter or click "Calculate Calories". The results show BMR, TDEE, a visual calorie range bar, goal targets, and a full activity sensitivity table.
- 7Switch goals interactively: Click any goal card in the results to switch targets without recalculating. Press Esc or Reset All to clear.
Example Calculation
Profile: Male, 30 years old, 180 cm, 80 kg, moderately active (gym 4×/week). Using all three formulas:
| Formula | BMR | TDEE (×1.55 Moderate) |
|---|---|---|
| Mifflin-St Jeor | 1,875 kcal | 2,906 kcal |
| Harris-Benedict | 1,933 kcal | 2,966 kcal |
| Katch-McArdle (15% BF) | 1,887 kcal | 2,925 kcal |
Goal calorie targets using Mifflin-St Jeor TDEE ≈ 2,906 kcal:
| Goal | Daily Calories | Weekly Change | Protein Target |
|---|---|---|---|
| Lose Fast | TDEE − 750 kcal | −0.7 kg/week | 2.2–2.6 g/kg |
| Lose Weight | TDEE − 500 kcal | −0.5 kg/week | 2.0–2.4 g/kg |
| Maintain | TDEE ± 0 kcal | ±0 kg | 1.6–2.0 g/kg |
| Lean Gain | TDEE + 250 kcal | +0.25 kg/week | 1.8–2.4 g/kg |
| Bulk | TDEE + 500 kcal | +0.5 kg/week | 1.8–2.2 g/kg |
Why different formulas give different results
Understanding Calorie | TDEE & Weight Goals
What is TDEE and why does it matter?
TDEE is the single most important number for managing body weight. Every nutrition strategy, intermittent fasting, keto, low-carb, high-protein, works through the same mechanism: creating a calorie deficit or surplus relative to TDEE. Knowing your number removes guesswork and lets you set targets backed by energy balance, not faith.
- ›Below TDEE → calorie deficit → body draws on stored fat (and some muscle) for energy
- ›At TDEE → energy balance → weight remains stable
- ›Above TDEE → calorie surplus → body stores excess energy as fat (and some muscle if training)
Comparing the three BMR formulas
All three equations estimate BMR from measurable inputs, but they were developed on different populations. No formula is perfect, BMR estimates carry inherent error because metabolic rates vary between individuals with identical stats. Treat the output as a starting point.
| Formula | Published | Inputs | Best For | Typical Error |
|---|---|---|---|---|
| Mifflin-St Jeor | 1990 | Weight, height, age, sex | General population | ±10% |
| Harris-Benedict | 1919 / 1984 | Weight, height, age, sex | Clinical & hospital use | ±12% |
| Katch-McArdle | 1996 | Lean body mass (LBM) | Athletes, known body fat % | ±8% with accurate BF% |
Which formula should you use?
Activity multipliers, the most common source of error
The activity multiplier is often the largest source of inaccuracy in TDEE estimates. Most people overstate their activity level. Use these guidelines carefully:
| Level | Multiplier | Who It Fits |
|---|---|---|
| Sedentary | ×1.20 | Office work, no structured exercise, few steps per day |
| Lightly Active | ×1.375 | Light cardio or weights 1–3×/week, mostly desk job |
| Moderately Active | ×1.55 | Gym or sport 3–5×/week, mixed desk and standing job |
| Very Active | ×1.725 | Hard training 6–7×/week or physical job plus exercise |
| Extra Active | ×1.90 | Manual labour all day plus regular intense training |
When in doubt, choose one level lower and track actual weight changes for two weeks. Raise the multiplier if you are losing weight faster than your deficit predicts.
The science behind calorie deficits and surpluses
One kilogram of body fat contains approximately 7,700 kcal of stored energy. A consistent deficit of 500 kcal/day produces roughly 0.5 kg of weight loss per week. In practice the rate slows as body weight drops because both TDEE and BMR decrease.
- ›A 500 kcal deficit is sustainable for most people, hunger is manageable and muscle loss is minimised with adequate protein.
- ›A 750 kcal deficit is appropriate for faster loss but requires strict tracking and higher protein to preserve muscle mass.
- ›Deficits above 1,000 kcal/day trigger adaptive thermogenesis, the body lowers TDEE to compensate, stalling progress over time.
- ›Small surpluses (250–500 kcal) paired with resistance training allow muscle gain with minimal fat accumulation.
Protein, the variable that changes everything
Protein has the highest satiety per calorie, the highest thermic effect of food (~25–30% of calories eaten are used in digestion), and is critical for preserving muscle during a deficit. The calculator provides protein ranges by goal, see the Macro Calculator to split remaining calories between carbohydrates and fats.
Realistic weight loss timeline
Weight loss is not linear. Fluctuations from water, glycogen, and gut content are normal. Judge progress over 2–3 week trends, not daily weigh-ins:
- ›Week 1–2: rapid drop (often 1–2 kg) from glycogen and water depletion, not fat
- ›Week 3 onward: consistent 0.25–0.75 kg/week fat loss depending on deficit size
- ›Plateaus: common after 8–12 weeks, recalculate TDEE at the new body weight
- ›Re-feeds: a 1–2 day break at maintenance every 4–6 weeks can restore leptin and improve adherence
Use the BMI Calculator and Ideal Weight Calculator to set a realistic target weight for your frame.
Limitations of online calorie calculators
- ›Thyroid disorders, PCOS, and medications can shift actual TDEE by 15–25%
- ›Muscle mass matters: two people at the same weight but different body compositions have very different BMRs, use Body Fat Calculator with Katch-McArdle for the most accurate result
- ›Activity multipliers assume sustained effort, most people are active for 1 hour but sedentary for the other 23
- ›Adaptive thermogenesis means extended deficits reduce TDEE below what any formula predicts
- ›The calculator does not account for the thermic effect of food (~10% of TDEE for mixed diets)
Frequently Asked Questions
How many calories should I eat to lose weight?
- ›Subtract 500 kcal from your TDEE for a moderate deficit, roughly 0.5 kg/week fat loss
- ›Never go below 1,200 kcal (women) or 1,500 kcal (men) without medical supervision
- ›A 20% deficit from TDEE is a safe and sustainable rule of thumb for most people
- ›Track for 2 weeks, then adjust by 100–200 kcal if actual weight change differs from predicted
- ›Higher protein intake (2.0–2.4 g/kg) preserves muscle during a calorie deficit
What is the difference between BMR and TDEE?
- ›BMR (Basal Metabolic Rate), calories your body burns completely at rest to sustain breathing, heartbeat, and cell repair. Accounts for 60–75% of TDEE in sedentary people.
- ›TDEE (Total Daily Energy Expenditure), BMR plus all movement, exercise, digestion, and incidental activity.
- ›Your food intake should be compared against TDEE, not BMR.
- ›The gap between BMR and TDEE widens with activity, a very active person may burn 1.9× their BMR each day.
Which BMR formula is most accurate, Mifflin, Harris-Benedict, or Katch-McArdle?
- ›Mifflin-St Jeor is the most validated for the general population across multiple independent studies.
- ›Harris-Benedict (1984 revision) is slightly less accurate for sedentary individuals but widely used in clinical settings.
- ›Katch-McArdle is most accurate for athletes and lean individuals when body fat % is precisely measured.
- ›All three carry ±8–12% error, none outperforms consistent tracking and real-world adjustment.
How do I calculate my calorie deficit?
- ›Calculate TDEE using this calculator
- ›Choose a daily calorie target below your TDEE (500 kcal less = moderate deficit)
- ›Calorie Deficit = TDEE − Daily Intake
- ›After 2 weeks, check: if you lost ≈0.5 kg, the deficit is accurate, if not, adjust by 100–200 kcal
- ›Never chase the largest possible deficit, metabolic adaptation and muscle loss make extreme deficits counterproductive
Can eating too few calories stall weight loss?
- ›Yes, extreme restriction triggers adaptive thermogenesis, where the body lowers TDEE by 10–25% to conserve energy
- ›Muscle loss from insufficient protein + very low calories reduces BMR further over time
- ›Weight loss stalls as TDEE adjusts downward, not because low calories cause fat gain
- ›Re-feeds at maintenance for 1–2 days every 4–6 weeks help restore leptin and keep metabolism responsive
- ›A moderate deficit (−500 kcal) is far more effective long-term than an aggressive one (−1,000+ kcal)
How long will it take me to reach my goal weight?
- ›Estimate: Weeks = (Target kg loss × 7,700) ÷ Daily Deficit (kcal)
- ›Example: lose 10 kg at 500 kcal/day deficit → 10 × 7,700 ÷ 500 = 154 days (~22 weeks)
- ›In practice, the rate slows as body weight drops, recalculate TDEE every 5 kg lost
- ›Week 1–2 losses are often inflated by water and glycogen, steady fat loss begins week 3+
- ›Slow loss (0.25–0.5 kg/week) typically preserves more muscle than fast loss
What is a good daily protein intake for weight loss?
- ›1.6–2.4 g of protein per kg of body weight per day is the evidence-based range for weight loss with muscle preservation
- ›Go to the higher end (2.2–2.6 g/kg) during aggressive deficits to protect muscle mass
- ›Protein has the highest satiety of all macronutrients, it keeps hunger lower on fewer calories
- ›Spread protein across 3–5 meals (30–40 g per meal) to maximise muscle protein synthesis
- ›Use the Macro Calculator to split remaining calories between carbs and fat once protein is set
Should I eat back calories burned during exercise?
- ›The activity multiplier already accounts for your regular exercise, do not add those calories back
- ›For occasional extra-long sessions beyond your normal routine, eating back 50% of the estimated burn is a reasonable buffer
- ›Wearables and gym machines significantly overestimate calorie burn, often by 20–70%
- ›If you chose Sedentary but exercise frequently, consider raising your multiplier rather than logging individual workouts