Calorie Calculator
Find your daily calorie needs (TDEE) for weight loss, maintenance, or muscle gain.
How the Calorie Calculator works
This calculator uses the Mifflin-St Jeor equation — the most accurate formula for estimating Basal Metabolic Rate (BMR) in adults. BMR is then multiplied by an activity factor to give your Total Daily Energy Expenditure (TDEE). The results also show suggested intakes for weight loss (−500 kcal/day deficit) and muscle gain (+300 kcal/day surplus).
Why the Calorie Calculator is Useful
"Eat less, move more" is technically correct advice for weight loss — but it's useless without a number. How much less? Less than what? Your body burns a specific amount of energy every day just to exist (your BMR), and then additional calories based on how active you are. Without knowing your personal TDEE, you're essentially guessing — and the gap between "I think I need 2,000 calories" and the actual number can easily be 300–500 calories in either direction, enough to stall progress for months. This calculator uses the Mifflin-St Jeor equation — the most validated formula for estimating calorie needs in adults — to give you a personalised TDEE. More usefully, it also gives you three actionable targets: your BMR (bare minimum), your weight-loss target (−500 kcal deficit for ~0.5 kg/week loss), and your muscle-gain target (+300 kcal surplus). One calculation, three immediately usable numbers.
Key Features
- Mifflin-St Jeor equation: The most accurate BMR formula for the general adult population, accounting for weight, height, age, and sex. More reliable than the older Harris-Benedict formula.
- Five activity levels: From sedentary (desk job, no exercise) to extra active (physical labour or two-a-day workouts), covering the full realistic range of daily energy expenditure.
- TDEE as the primary output: Your maintenance calories are prominently displayed — the number you eat at to stay exactly the same weight.
- Three derived targets: BMR (bare metabolic floor), Weight Loss target (TDEE − 500 kcal), and Muscle Gain target (TDEE + 300 kcal) — so you can move to your goal immediately.
- Safe minimum floor: The weight loss target is automatically capped at 1,200 kcal/day (women) and 1,500 kcal/day (men) to prevent the calculator from returning dangerously low recommendations.
Real-Life Use Cases
- Starting a diet: Before beginning any calorie-controlled eating plan, calculate your personal TDEE so you know the baseline you're working from — not an arbitrary generic number from an article online.
- Setting up a food tracking app: Apps like MyFitnessPal ask for a calorie target when you first set up. Use this calculator to get an accurate number rather than accepting the app's default recommendation.
- Pairing with the Macros Calculator: Take your TDEE from this tool and plug it into the Macros Calculator to break it down into protein, carbs, and fat targets for your specific goal.
- After significant weight change: TDEE isn't fixed — it changes as your weight changes. Recalculate every 4–6 weeks during a weight loss or gain programme to keep your targets accurate.
- Explaining energy balance to others: Personal trainers and coaches use TDEE calculations to help clients understand why their current eating habits are producing the results they're seeing.
Who Can Use This Tool
Anyone who wants a concrete calorie number to work from — whether you're starting a fat-loss programme, entering a muscle-building phase, trying to reverse-diet out of a plateau, or simply curious about how your daily energy needs compare to what you're actually eating. It's equally useful for complete beginners who have never tracked food before and for experienced athletes periodising their nutrition around a training calendar.
Tips & Best Practices
- Be honest about your activity level: Most people overestimate how active they are. If you work out 3 times a week but sit at a desk the rest of the time, "Moderately active" is likely the right choice — not "Very active". Overestimating activity inflates your TDEE and slows fat loss.
- Use TDEE as a starting point, not a law: The formula gives a statistically accurate estimate, not your exact number. Start at the calculated TDEE, track your weight for 2–3 weeks, and adjust up or down by 100–150 kcal if your weight isn't responding as expected.
- Combine with the Macros Calculator: Once you have your calorie target, the next step is knowing how to split those calories between protein, carbs, and fat. Follow the Macros Calculator link to get gram targets for your specific goal.
- Recalculate after 5+ kg of weight change: Every kilogram of body mass burns roughly 13–15 kcal/day at rest. After significant weight change, your TDEE shifts enough that your old targets may no longer be appropriate.
- Don't drop below minimum floors: Eating below 1,200 kcal/day (women) or 1,500 kcal/day (men) for extended periods risks nutrient deficiencies, metabolic adaptation, and muscle loss. If the weight-loss target feels extremely low, reduce your deficit to −300 kcal instead of −500.