What is TDEE and how is it calculated?

TDEE stands for Total Daily Energy Expenditure — the total number of calories your body burns in a day. It is calculated by first estimating your Basal Metabolic Rate (the calories burned at rest) using the Harris-Benedict or Mifflin-St Jeor equation, then multiplying it by an activity factor that reflects how much you move. TDEE is the calorie intake at which your weight stays stable.

How many calories should I eat to lose weight?

To lose weight sustainably, aim for a calorie deficit of 300–500 calories below your TDEE. A 500-calorie daily deficit produces approximately 0.5 kg (1 lb) of fat loss per week, which is considered a safe and sustainable rate. Deficits larger than 1,000 calories per day risk significant muscle loss, micronutrient deficiencies, and metabolic adaptation.

How many calories does a woman need per day?

Most adult women need between 1,600 and 2,400 calories per day, depending on age, height, weight, and activity level. Sedentary women in their 30s typically need around 1,800–2,000 calories. Active women or those doing significant exercise may need 2,200–2,600. The calorie calculator above gives you a personalised estimate based on your specific stats.

How many calories should a man eat per day?

Most adult men need between 2,000 and 3,000 calories per day. A sedentary man in his 30s typically needs around 2,200–2,500 calories to maintain weight. Very active men — those doing intense daily exercise — may need 3,000–4,000 calories. Use the calculator above with your actual stats and activity level for a precise personalised estimate.

What activity level should I choose?

Choose Sedentary if you have a desk job and do little formal exercise. Lightly Active suits 1–3 days of light exercise per week. Moderately Active fits 3–5 days of moderate exercise. Very Active is for 6–7 days of hard exercise. Extra Active is for athletes, physical labourers, or those training twice a day. Most people underestimate their activity level — if in doubt, choose one level lower and adjust based on results.

Is a 500 calorie deficit safe?

Yes — a 500-calorie daily deficit is widely considered safe and effective for most healthy adults. It produces approximately 0.45 kg (1 lb) of fat loss per week and is large enough to drive consistent results without triggering significant metabolic adaptation or muscle loss. It should be achieved primarily through moderate dietary reduction, with exercise used to improve health rather than simply burn calories.

How many calories do I need to build muscle?

Building muscle requires a calorie surplus above your TDEE — typically 200–500 extra calories per day for most natural trainees. A modest surplus of 300 calories per day minimises fat gain while providing enough energy for muscle protein synthesis. Combined with progressive resistance training and adequate protein (1.6–2.2 g per kg of bodyweight), this produces lean muscle gains of approximately 0.5–1 kg per month for beginners.

🔥 Calorie Calculator — Find Your Daily Calorie Needs (TDEE)

Calculate your Total Daily Energy Expenditure and daily calorie target for weight loss, maintenance, or muscle gain.

Sex

Age (years)

Height (cm)

Weight (kg)

Activity Level

Goal

Quick Calorie Facts

2,000–2,500

Average adult daily calorie need

500 cal/day

Deficit needed to lose 1 lb per week

25–30%

Calories from protein recommended

1.2–1.9×

BMR multiplier for activity level

1919

Year Harris-Benedict equation was published

Sources: Harris & Benedict (1919), Mifflin et al. (1990)

How It Works

How the Harris-Benedict Equation Calculates Your BMR

TDEE formula diagram showing BMR plus activity multipliers

Your Basal Metabolic Rate (BMR) is the number of calories your body burns at complete rest to sustain life — breathing, circulation, cell production, and temperature regulation. The Harris-Benedict equation, first published in 1919 and revised in 1984, estimates BMR from your sex, age, height, and weight:

Male BMR = 88.362 + (13.397 × kg) + (4.799 × cm) − (5.677 × age)
Female BMR = 447.593 + (9.247 × kg) + (3.098 × cm) − (4.330 × age)

Your TDEE is calculated by multiplying your BMR by an activity factor. This gives your calorie maintenance level — the intake at which your weight stays stable. Eating below TDEE creates a deficit; eating above creates a surplus.

Activity Level Multipliers

1.2×

Sedentary

Desk job, no formal exercise, mostly sitting

1.375×

Lightly Active

1–3 days of light exercise or sport per week

1.55×

Moderately Active

3–5 days of moderate exercise per week

1.725×

Very Active

6–7 days of hard training or physical work

1.9×

Extra Active

Twice-daily training or very heavy physical labour

Estimated Daily Calorie Needs by Age and Activity

Based on average height and weight. Use the calculator above for your personalised figure.

Age Group	Men — Sedentary	Men — Active	Women — Sedentary	Women — Active
19–30	2,400 cal	3,000 cal	1,800 cal	2,400 cal
31–50	2,200 cal	2,800 cal	1,800 cal	2,200 cal
51–70	2,000 cal	2,600 cal	1,600 cal	2,000 cal
71+	2,000 cal	2,400 cal	1,600 cal	2,000 cal

Source: Dietary Guidelines for Americans 2020–2025, USDA.

Frequently Asked Questions

TDEE stands for Total Daily Energy Expenditure — the total calories your body burns in a day including all activity. It is calculated by first estimating your Basal Metabolic Rate (calories burned at rest) using the Harris-Benedict or Mifflin-St Jeor formula, then multiplying by an activity factor. TDEE is the calorie intake at which your weight stays perfectly stable. Eating above TDEE creates a surplus that promotes muscle and fat gain; eating below creates a deficit that drives fat loss.

For sustainable fat loss, aim for a 300–500 calorie daily deficit below your TDEE. A 500-calorie deficit produces approximately 0.45 kg (1 lb) of fat loss per week. This rate is considered safe for most healthy adults and is slow enough to preserve muscle mass. Avoid deficits larger than 750–1,000 calories per day — they trigger metabolic adaptation (your body burning fewer calories) and significantly increase muscle loss, making long-term success much harder.

BMR is the number of calories your body burns at complete rest — the energy required just to keep you alive: breathing, circulation, cell production, digestion, and temperature regulation. It accounts for 60–75% of total calorie expenditure for sedentary people. BMR is higher in people with more lean muscle mass (muscle burns roughly 6 cal/lb/day vs 2 cal/lb/day for fat) and decreases about 1–2% per decade after age 20 due to age-related muscle loss.

Most adult women need between 1,600 and 2,400 calories per day, depending on age, height, weight, and activity level. A sedentary woman in her 30s at average height and weight typically needs around 1,800–2,000 calories. Active women doing 5+ hours of exercise per week may need 2,200–2,600. Pregnant women need an additional 300–500 calories daily in the second and third trimester. The personalised calculator above provides a more precise estimate.

Most adult men need between 2,000 and 3,000 calories per day. A sedentary man in his 30s at average height and weight typically needs around 2,200–2,500 calories to maintain weight. Men doing significant exercise — 5+ sessions per week — may need 2,800–3,500. Elite endurance athletes or those in physical labour can exceed 4,000 calories. Individual needs vary widely; use the calculator above with your actual stats for a personalised target.

Select Sedentary if you have a desk job and do little formal exercise outside of daily movement. Lightly Active suits one to three days of moderate exercise per week. Moderately Active fits three to five days of deliberate exercise. Very Active applies to six or seven days of hard training. Extra Active is reserved for athletes training twice daily or people in intensive manual labour. Research consistently shows most people underestimate their sedentariness — if unsure, go one level below your instinct and adjust based on results over 2–3 weeks.

Yes — a 500-calorie daily deficit is widely considered safe and effective for most healthy adults without underlying medical conditions. It drives approximately 0.45 kg (1 lb) of fat loss per week while largely preserving muscle mass, especially when combined with sufficient protein intake (1.6 g per kg bodyweight) and resistance training. The deficit should come primarily from dietary reduction, not extreme exercise, to avoid chronic energy availability problems that impair hormonal health.

Effective muscle building requires a modest calorie surplus above TDEE — typically 200–500 calories per day. A surplus of 300 calories minimises fat gain while providing adequate energy for muscle protein synthesis. Without sufficient calories, the body cannot build new tissue even with heavy training. Combined with progressive resistance training and protein intake of 1.6–2.2 g per kg, a 300-calorie surplus supports natural muscle gains of approximately 0.5–1 kg per month for beginners, and 0.25–0.5 kg per month for intermediate trainees.

Calorie Calculator for Weight Loss — How Big a Deficit Is Safe?

The most common weight loss mistake is creating a deficit that is too large. A 1,000+ calorie daily deficit feels faster in theory, but research consistently shows it accelerates muscle loss, triggers metabolic adaptation (where your body lowers its resting energy expenditure), and leads to rebound weight gain in the majority of cases within two years.

A well-designed deficit of 400–600 calories — roughly 20–25% below TDEE — produces steady fat loss while preserving muscle when combined with adequate protein and resistance training. At this rate, someone with 10 kg to lose would reach their goal in approximately 20–25 weeks. This is not slow — it is the speed at which fat loss sticks permanently.

TDEE Calculator for Women — Why Calorie Needs Differ by Sex

Women's calorie needs are genuinely lower than men's at equivalent height, weight, and activity — not due to any metabolic disadvantage, but because women typically carry proportionally more body fat and less lean muscle mass. Since muscle tissue burns approximately three times more calories at rest than fat tissue, the difference in body composition directly reduces TDEE.

Additionally, women's calorie needs fluctuate across the menstrual cycle by approximately 100–300 calories per day, rising in the luteal phase (after ovulation) as progesterone increases resting metabolic rate. This is a well-documented physiological phenomenon and is one reason why appetite, hunger, and energy naturally vary across the month. Tracking calories rigidly without accounting for this cycle can be counterproductive.

Calorie Calculator for Muscle Gain — Eating in a Surplus

Building muscle is a slow, energetically expensive process. Even in optimal conditions — heavy resistance training, ideal nutrition, adequate sleep — a natural trainee can only build 0.5–2 kg of muscle per month. This means the energy surplus required is modest: 200–500 extra calories per day is sufficient.

A common mistake is "dirty bulking" — eating in a large surplus of 700–1,000+ calories per day. While it accelerates scale weight gain, a significant portion of that gain is fat, not muscle. This requires an extended cut phase to reverse, often resulting in net muscle gain no greater than a more modest approach. A "lean bulk" of +300 calories, high protein, and progressive training maximises the muscle-to-fat ratio of weight gained.

Calorie Calculator: The Science Behind Energy Balance

Calorie balance — the relationship between energy consumed and energy expended — is the fundamental driver of body weight change. While the "calories in, calories out" model is frequently criticised as oversimplistic (and it is, in certain nuanced contexts), decades of controlled metabolic ward research confirm that no one has gained or lost weight in a genuine calorie balance. The debate is not about whether energy balance matters, but about the many factors that influence it.

Why Calorie Tracking Is Harder Than It Looks

Food labelling regulations in many countries allow a ±20% error margin on stated calorie counts. Restaurant meals are consistently under-reported in studies, sometimes by 40–100%. Most people also underestimate portion sizes. These real-world inaccuracies mean your actual intake may differ significantly from tracked intake — one reason why self-reported dietary data is notoriously unreliable in nutrition research. Using calorie counts as estimates — not precise figures — is the right frame.

Non-Exercise Activity Thermogenesis (NEAT)

The most variable component of TDEE is NEAT — all the non-exercise movement in a day: fidgeting, walking, standing, housework, gesturing. Research by Dr. James Levine at the Mayo Clinic found NEAT varies by up to 2,000 calories per day between individuals of similar size. When people overeat, NEAT often unconsciously rises; when they undereat, it falls. This explains why two people with the same TDEE calculation respond differently to the same deficit — and why the calculator's output is a starting point, not a final answer.

Disclaimer: This calorie calculator provides an estimate based on established equations and is intended for general informational use. Individual calorie needs vary. Consult a registered dietitian or physician before making significant changes to your diet, especially if you have a medical condition.