🔥 Free Calorie Calculator
Find your daily calorie needs for weight maintenance, fat loss, or muscle gain. Enter your details below for instant, personalized results.
What is this tool?
Wondering how many calories you should eat each day? Our free calorie calculator gives you a personalized answer in seconds. Using the validated Mifflin-St Jeor equation, it estimates your Basal Metabolic Rate (BMR) — the calories your body needs at complete rest — and then factors in your daily activity level to calculate your Total Daily Energy Expenditure (TDEE). From there, it automatically shows three calorie targets side by side: maintenance (keep your current weight), mild weight loss (a safe 500-calorie deficit for dropping about 0.5 kg per week), and weight gain (a controlled surplus for building muscle).
What makes Muxtly's daily calorie calculator different from other online tools? It runs entirely in your browser — no data is uploaded to any server, so your privacy is guaranteed. The three-target layout lets you compare your options at a glance rather than running separate calculations. Whether you are planning a diet, tracking your macros, or simply curious about your daily caloric needs, this tool gives you the numbers you need without ads, sign-ups, or distractions.
How it works
Your daily calorie needs are calculated in three clear steps: first we compute your BMR (the energy your body requires at rest), then we adjust for your physical activity level to find your TDEE, and finally we apply your goal adjustment (deficit for fat loss or surplus for muscle gain).
Step 1 — Basal Metabolic Rate (BMR)
BMR represents roughly 60–75% of your total daily energy expenditure and is estimated using the Mifflin-St Jeor equation, the formula most widely recommended by dietetics professionals. It differs for men and women because men typically have more lean muscle mass:
For example, a 30-year-old man weighing 75 kg with a height of 175 cm has a BMR of 10 × 75 + 6.25 × 175 – 5 × 30 + 5 = 1,704 kcal per day. That is how many calories his body burns before any physical activity is considered.
Step 2 — Total Daily Energy Expenditure (TDEE)
To find your true daily calorie expenditure, we multiply your BMR by an activity multiplier that reflects how much you move throughout the week. Someone who is sedentary burns far fewer calories than a construction worker or a competitive athlete. Our calorie needs calculator uses five activity tiers, each with a clinically validated coefficient:
| Activity Level | Description | Multiplier |
|---|---|---|
| Sedentary | Little or no exercise, desk job | × 1.2 |
| Lightly active | Light exercise 1–3 days/week | × 1.375 |
| Moderately active | Moderate exercise 3–5 days/week | × 1.55 |
| Very active | Hard exercise 6–7 days/week | × 1.725 |
| Super active | Intense daily exercise or physical job | × 1.9 |
Continuing the example: if that 30-year-old man is moderately active, his TDEE = 1,704 × 1.55 = 2,641 kcal per day. That is the number of calories he needs to eat to maintain his current weight.
Step 3 — Goal Adjustment
Once we have your TDEE, the tool applies three goal-specific adjustments so you can see your options side by side:
- Maintenance calories = TDEE (no change)
- Mild weight loss = TDEE – 500 kcal (safe deficit for ~0.5 kg/week fat loss)
- Weight gain = TDEE + 300 kcal (controlled surplus for lean muscle gain)
Because 1 lb (≈0.45 kg) of body fat stores roughly 3,500 calories, a daily deficit of 500 calories leads to about 1 lb of fat loss per week — a pace widely regarded as safe and sustainable by the CDC and the National Institutes of Health.
How to use
- Select your gender — Choose Male or Female. The Mifflin-St Jeor formula uses different constants for each, so this ensures your BMR is calculated correctly.
- Enter your age — Type your age in years (10–120). Age is a critical factor because your resting metabolic rate naturally declines with age, primarily due to changes in muscle mass.
- Enter your weight and height — You can switch between metric (kg / cm) and imperial (lb / ft + in) using the unit dropdowns next to each field. The tool converts everything automatically before running the calculation.
- Select your activity level — Choose the option that best matches your typical weekly exercise routine. If you are unsure, the "Moderately active (3–5 days/week)" setting is a good starting point for most people who exercise regularly.
- Click Calculate — The tool instantly displays your BMR, your TDEE, and all three calorie targets: maintenance, mild weight loss, and weight gain. Use these numbers to plan your daily meals, track against your goals, or share with a dietitian.
Reference Table
Use the table below to understand which activity level best describes your lifestyle. Choosing the right level is important because it directly affects your daily calorie needs.
| Level | Description | Coefficient | Example Occupations / Routines |
|---|---|---|---|
| Sedentary | Little or no exercise; desk-based job | 1.2 | Office worker, driver, remote desk job |
| Lightly active | Light exercise 1–3 days per week | 1.375 | Casual walking, yoga, leisurely cycling |
| Moderately active | Moderate exercise 3–5 days per week | 1.55 | Jogging, gym 3–4×/week, recreational sports |
| Very active | Hard exercise 6–7 days per week | 1.725 | Daily gym, competitive sports, physical training |
| Super active | Intense daily exercise or physically demanding job | 1.9 | Athlete in training, construction worker, farming |
If you exercise most days but also have a sedentary job, start with the "Very active" level and adjust down if you are not seeing the expected results over a couple of weeks.
Frequently Asked Questions
How many calories should I eat to lose weight?
To lose weight safely, aim for a calorie deficit of 300–500 calories below your TDEE. This typically translates to a weight loss rate of 0.3–0.5 kg (0.6–1 lb) per week. For most women, this means eating roughly 1,500–1,800 calories per day, and for most men about 1,800–2,200 calories per day, though individual numbers vary. Use this calorie deficit calculator feature above — the "Mild Weight Loss" target automatically subtracts 500 calories from your TDEE. Never drop below 1,200 calories (women) or 1,500 calories (men) unless supervised by a healthcare professional, as extremely low intakes can slow your metabolism and cause nutrient deficiencies.
What is the difference between BMR and TDEE?
Your BMR (Basal Metabolic Rate) is the minimum energy your body needs to stay alive — breathing, circulating blood, and regenerating cells. It makes up 60–75% of your total calorie burn. Your TDEE (Total Daily Energy Expenditure) is the full picture: BMR plus all the calories you burn through movement, exercise, and digesting food. In practical terms, BMR tells you what your body needs at rest; TDEE tells you what to eat to maintain your current weight. Both numbers are shown in the results above.
Is this formula accurate for everyone?
The Mifflin-St Jeor equation is one of the most accurate calorie intake calculator formulas available for the general population, with a typical error margin of about ±10%. It was developed by Mifflin et al. in 1990 and remains the gold standard recommended by the Academy of Nutrition and Dietetics. That said, no formula can account for every individual variable. People with very high muscle mass, metabolic conditions, or those taking certain medications may have real-world needs that differ from the estimate. Treat the result as an excellent starting point, then track your weight over 2–3 weeks and adjust by roughly 100–200 calories as needed.
Can I use this for muscle gain?
Absolutely. Building muscle requires a calorie surplus, and the "Weight Gain" target of TDEE + 300 calories in this calculator is specifically designed for lean muscle gain at a steady rate of about 0.3 kg (0.6 lb) per week. For best results, pair your surplus with a progressive strength training program and a protein intake of 1.6–2.2 grams per kilogram of body weight daily. Avoid excessive surpluses above TDEE + 500, as the extra energy is more likely stored as body fat rather than used for muscle synthesis.
Tips & Advice
Your daily calorie intake is only one piece of the health puzzle. For sustainable weight management, focus on food quality as much as quantity — prioritize lean proteins, whole grains, vegetables, healthy fats, and fiber-rich foods that keep you full and energized. Combine a moderate calorie deficit or surplus with regular physical activity: strength training preserves muscle during weight loss, while cardio supports heart health and additional calorie burn.
Stay hydrated and aim for 7–9 hours of quality sleep per night, since poor sleep can disrupt hunger hormones like ghrelin and leptin, making it harder to stick to your goals. Track your progress with weekly weigh-ins and measurements rather than daily fluctuations, which are heavily influenced by water retention. Finally, remember that these calorie needs are estimates — listen to your body and adjust based on your energy levels, appetite, and how your clothes fit. For personalized medical or dietary advice, always consult a registered dietitian or healthcare provider.