Calorie Calculator
How to calculate your daily calorie needs
Three quick steps from your details to a calorie target, deficit plan and macros.
Enter gender, age, height and weight in US, metric or UK units. These set the energy your body burns at rest, the foundation of your daily calorie needs.
Pick the activity level that matches your week and whether you want to maintain, lose or gain. Your goal sets the deficit or surplus and the macro split.
See your recommended daily calories, deficit and surplus tiers, your weekly weight projection and protein, carb and fat targets — then save a PDF.
Calorie Calculator — Plan Every Calorie With Confidence
A calorie is simply a unit of energy, and managing your weight comes down to the balance between the calories you eat and the calories you burn. This calculator works out your daily calorie needs for any goal, then goes further than most: it shows graded deficit tiers for losing weight, a surplus for gaining, a projected weekly weight change, and a full protein, carb and fat breakdown. It uses the validated Mifflin-St Jeor equation with an activity multiplier and runs entirely in your browser, in US, metric or UK units.
Calorie intake and calorie expenditure
Every day your body spends energy in three main ways: your resting metabolism (the largest share), the calories burned digesting food, and the calories burned moving. Together these make up your total daily energy expenditure, or maintenance level. Calorie intake is simply the energy you take in from food and drink. When intake matches expenditure your weight holds steady; tip the balance one way or the other and your weight follows. Understanding both sides of that equation is the whole game, and this tool quantifies it for you.
Energy balance and how weight changes
Weight change is governed by energy balance. Eat fewer calories than you burn and your body makes up the shortfall from its stores, mostly fat, so you lose weight. Eat more and the surplus is stored, ideally as muscle if you train. Because roughly 7,700 calories are stored in a kilogram of body fat, a daily deficit of 500 calories — about 3,500 a week — produces close to half a kilogram of loss. The principle is simple, but the right size of deficit or surplus is where this calculator helps you avoid common mistakes.
Weight loss planning with calorie deficits
For fat loss the tool shows three deficit tiers: mild (250 calories below maintenance), moderate (500) and aggressive (750). A moderate deficit is the classic recommendation because it loses fat at a steady, sustainable pace while leaving enough food to preserve muscle and energy. Aggressive deficits work faster but raise the risk of muscle loss, hunger, low energy and rebound, so they suit shorter pushes rather than long campaigns. Whatever tier you choose, keeping protein high and training with resistance ensures the weight you lose is fat rather than muscle.
Muscle gain planning with calorie surpluses
Building muscle requires both a training stimulus and slightly more energy than you burn. The calculator's gain target adds a modest surplus to maintenance, enough to support growth without piling on excess fat. Pair it with progressive strength training and ample protein and the surplus is channelled into new muscle. Gaining too fast simply adds fat you will later have to lose, so a measured surplus and patience produce a leaner, more durable result. Track your weekly weight and trim the surplus if the scale climbs faster than planned.
Nutrition planning with macros
Calories decide whether you lose, hold or gain; macronutrients decide how good you feel and what kind of weight you carry. This calculator splits your target into protein, carbohydrate and fat using goal-based ratios — higher protein when losing to protect muscle, balanced for maintenance, and carb-forward when gaining to fuel training. Protein and carbohydrate each provide four calories per gram and fat provides nine, so the percentages translate into concrete daily gram targets. Hitting your calories keeps you on track for weight; hitting your macros keeps that progress healthy and sustainable. Everything is computed locally; your details are never uploaded or stored.
Why use this calorie calculator?
A full calorie-planning platform — targets, deficit tiers, projection and macros in one view.
A single recommended calorie number tuned to whether you want to maintain, lose or gain — no guesswork about how much to adjust.
Mild, moderate and aggressive loss tiers plus a gain target, so you can match the pace to your timeline and lifestyle.
See the estimated weekly weight change at your chosen target, so your plan comes with realistic expectations from day one.
Protein, carb and fat targets in grams, tuned to your goal — turning a calorie number into an actual nutrition plan.
A clean chart lines up loss, maintenance and gain so you can see your options side by side at a glance.
Download a branded report with your calorie targets, goal analysis and macro breakdown — a plan you can keep and follow.
Calorie deficit and surplus analysis
How far below or above maintenance to eat — and what each choice means for your pace.
| Plan | Daily change | Weekly result | Best for |
|---|---|---|---|
| Mild deficit | −250 kcal | ≈ 0.25 kg loss | Easy, very sustainable cut |
| Moderate deficit | −500 kcal | ≈ 0.5 kg loss | The standard fat-loss pace |
| Aggressive deficit | −750 kcal | ≈ 0.7 kg loss | Short pushes, higher risk |
| Maintenance | 0 kcal | Weight holds | Holding or recomposition |
| Surplus | +400 kcal | ≈ 0.4 kg gain | Muscle and weight gain |
Choosing your deficit
A moderate 500-calorie deficit is the classic recommendation: fast enough to see progress, gentle enough to preserve muscle and energy. Bigger deficits lose weight quicker but bring more hunger, fatigue and muscle-loss risk, so they suit short, focused phases. Never sit far below your resting needs for long without professional guidance.
Making a surplus count
For gaining, a modest surplus adds weight steadily while limiting fat gain. The extra energy only becomes muscle if you train for it, so pair the surplus with progressive resistance work and plenty of protein. Watch the scale weekly — if it climbs faster than planned, the surplus is too large and is adding fat.
Macro splits by goal
Once your calories are set, these ratios divide them into protein, carbs and fat.
| Goal | Carbs | Protein | Fat |
|---|---|---|---|
| Lose weight | 40% | 40% | 20% |
| Maintain weight | 50% | 25% | 25% |
| Gain weight / muscle | 45% | 30% | 25% |
| Calories per gram | 4 kcal | 4 kcal | 9 kcal |
Why protein rises when cutting
In a deficit your body can break down muscle for energy, so the loss plan uses a higher protein share to protect lean tissue. Protein is also the most filling macro and burns the most calories during digestion, which makes a calorie deficit easier to stick to. Aim to spread it across your meals through the day.
Carbs, fat and how to convert
Carbohydrates fuel training and brain function; fat supports hormones and nutrient absorption, so neither should be cut to zero. To turn a percentage into grams, multiply your calorie target by the percentage, then divide by 4 for protein and carbs or by 9 for fat. This calculator does that maths for you automatically.
Related health calculators
Calories are the foundation — pair them with these to round out your plan.
Frequently asked questions
Short, practical answers to the questions people ask most about calorie planning.
It depends on your size, age, sex, activity and goal. This calculator first finds your maintenance calories — the amount that holds your weight steady — by estimating the energy you burn at rest and multiplying by an activity factor. To lose weight you eat below that number; to gain, above it. Most adults land between 1,600 and 3,000 calories a day, but your personal figure appears the moment you enter your details.
A calorie deficit means eating fewer calories than you burn, which forces your body to use stored energy and lose weight. A deficit of about 500 calories a day produces roughly half a kilogram of fat loss per week. This tool shows mild (250), moderate (500) and aggressive (750) tiers. Larger deficits lose weight faster but risk muscle loss, fatigue and rebound, so steadier is usually better.
A surplus means eating more calories than you burn, giving your body the extra energy to build tissue. For weight or muscle gain, a surplus of roughly 300 to 500 calories a day supports steady gains of about half a kilogram a week. Pair the extra calories with resistance training and enough protein so the gain is muscle rather than fat. A smaller surplus produces a leaner, slower gain.
Macros split your calorie target into protein, carbohydrate and fat. This calculator uses goal-based ratios: for weight loss a higher-protein 40% carb / 40% protein / 20% fat split to preserve muscle; for maintenance a balanced 50/25/25; and for gaining 45% carb / 30% protein / 25% fat to fuel training. Protein and carbs supply 4 calories per gram and fat 9, so the percentages convert into daily gram targets. Our macro calculator goes deeper.
Roughly one kilogram of body fat stores about 7,700 calories, so your weekly deficit or surplus divided by that figure estimates your weekly weight change. A 500-calorie daily deficit is about half a kilogram a week. The calculator shows your projected weekly change for the tier you pick. Real progress varies with water, glycogen and adherence, so judge it over several weeks rather than day to day.
No — they are well-informed estimates. The calculator uses the validated Mifflin-St Jeor equation plus an activity multiplier, which is accurate for most people but cannot account for your exact metabolism, muscle mass or daily movement. Treat the result as a starting point, eat at your target for two to four weeks, track your average weight, and adjust by 100 to 200 calories based on what actually happens. For the resting-rate detail, see our BMR calculator.