MyGymCalcUse it for a calorie deficit for weight loss, maintenance calories to hold your weight, or a calorie surplus for muscle gain.
What is a calorie calculator?
A calorie calculator estimates how many calories your body burns in a day, then shows you how many calories to eat based on your goal. This free calorie calculator uses your age, sex, height, weight and activity level to calculate your Total Daily Energy Expenditure (TDEE), the number of calories your body needs to maintain its current weight. From there it gives you three targets: how many calories to eat to maintain your weight, how many to eat in a deficit to lose fat, and how many to eat in a surplus to build muscle.
Unlike a basic BMR calculator, which only estimates the calories your body burns at rest, this daily calorie calculator factors in how active you are — whether you sit at a desk all day or train five times a week. That makes the result far more useful for planning your actual diet.
What is TDEE?
TDEE stands for total daily energy expenditure: the calories your body uses in an entire day. It combines your basal metabolic rate (BMR) — what you burn lying in bed doing absolutely nothing — with the energy spent digesting food, training and everything else you do.
Knowing that number is the single most useful thing you can know before changing your diet. Eat below it and you lose weight, eat above it and you gain it, eat at it and the scale stays put. Guessing is how most people spin their wheels for months.
How many calories should I eat a day?
The honest answer is: it depends on your body, your activity level and your goal — exactly what this calculator solves for. As a general guide, most adults need somewhere between 1,800 and 3,000 calories a day, but two people of the same height and weight can have very different needs if one trains six days a week and the other doesn’t exercise at all.
Enter your stats above and this calorie calculator gives you a personalised number instead of a generic guess. It also breaks the result into a range: a maintenance number to keep your weight stable, a lower number if your goal is fat loss, and a higher number if your goal is muscle gain.
Maintenance calories explained
Your maintenance calories, also called your TDEE, is the number of calories you would need to eat to keep your weight exactly where it is. This calorie calculator estimates it using your Basal Metabolic Rate (BMR), the calories your body burns just to function, and multiplies it by an activity factor based on how often you train or move during the day.
Knowing your maintenance number first matters because every other target, whether for losing fat or gaining muscle, is built on top of it. Get this number wrong and your deficit or surplus will be wrong too.
Calorie calculator for weight loss (calorie deficit)
To lose weight you need to eat fewer calories than you burn, known as a calorie deficit. This calorie calculator for weight loss takes your maintenance number and subtracts a moderate amount — typically enough to lose about 0.5 to 1% of your body weight per week, a safe, sustainable pace that preserves muscle while you lose fat.
A common mistake is cutting calories too aggressively. A very large deficit can lead to muscle loss, low energy and a slower metabolism over time. This tool sets cutting at maintenance − 20%, a moderate deficit that loses roughly 0.5% of body weight per week while keeping strength in the tank. Use that number as a starting point and adjust based on your actual progress over two to three weeks.
Calorie calculator for muscle gain (calorie surplus)
To build muscle you generally need to eat more calories than you burn, known as a calorie surplus. This calculator adds a modest amount on top of your maintenance calories — bulking at maintenance + 10% — enough to support muscle growth without adding excess fat. Combined with consistent resistance training and enough protein, this surplus target gives your body the fuel it needs to build new muscle tissue.
Which formula does this calorie calculator use?
The tool runs on the TDEE method. We first calculate BMR with the Mifflin-St Jeor equation, published in 1990 and widely considered one of the most accurate formulas for estimating BMR in both research and clinical use:
BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5 (men)
BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161 (women)
Your BMR is then multiplied by an activity factor, ranging from 1.2 for sedentary days up to 1.9 for double-shifts of training and physical work, to give your TDEE. This is the same method used across most reputable daily calorie calculators online, and it is a strong estimate for most adults — though individual metabolism can vary by a few percent in either direction.
We deliberately avoid extreme deficits. Aggressive cuts cost muscle, hormones and sanity, and the only thing they save is a few days.
Food calorie calculator vs. daily calorie calculator
It is worth clarifying the difference, since both get searched under similar terms. A food calorie calculator usually refers to a tool or app that looks up the calorie content of specific foods or meals, useful when you are logging what you eat. This tool is a daily calorie calculator: it tells you your overall calorie target for the day based on your body and goals, which you can then use alongside any food-tracking app of your choice to hit that number.
How to use your result
Start by eating your maintenance number for two weeks and watching the trend, not a single weigh-in. Weight moves up and down with carbs, sodium and training volume, so daily fluctuations of 1–2 kg are noise.
Once the trend is stable, pick a goal. Use the cutting number if your goal is fat loss, the bulking number if you are chasing size, and maintenance if you want to recomp.
Tips for using your calorie results
- Treat the number as a starting point, not a fixed rule. Track your weight over two to three weeks and adjust by 100–200 kcal if the weekly average is not moving the way you want.
- Pair your calorie target with the Macro Calculator to see exactly how much protein, carbs and fat to eat.
- Re-run the calculator every 10–15 lb (4–5 kg) of weight change, since your needs shift as your body changes.
- Combine this free calorie calculator with consistent training and enough sleep for the best results.
And remember the number is an estimate: your job is to test it against real-world results, not to obey it. Recalculate every month or every 4–5 kg of change, and adjust by 100–200 kcal when the average stops moving in the direction you want.