Calorie Deficit Calculator
Use this calorie deficit calculator to find your maintenance calories and a daily calorie target for steady, sustainable weight loss.
General nutrition education only. Not medical advice.
Quick answer: how to use this result
A calorie deficit calculator answers one practical question: how many calories should you eat each day to lose weight at a pace you can sustain? Enter your details above, and the tool estimates your maintenance calories (the amount that keeps your weight stable), then subtracts your chosen deficit to give a daily calorie target. Eat close to that target most days, check your weekly average weight after two to three weeks, and adjust by 100–150 calories if progress is faster or slower than expected. That is the whole method — the rest of this page explains why it works and how to avoid the common traps.
What a calorie deficit means
A calorie deficit simply means eating fewer calories than your body burns in a day. Your body makes up the shortfall by drawing on stored energy — mostly body fat — which is why a consistent deficit leads to weight loss over time. It is the common mechanism behind every diet that works, whether it is low-carb, intermittent fasting, or portion control with everyday desi meals: each one is a different way of arranging food so you naturally eat below your maintenance level.
The size of the deficit determines the pace. Roughly 7,700 calories corresponds to one kilogram of body fat, so a 500-calorie daily deficit works out to about half a kilogram per week. That number is an approximation — real-world weight change also reflects water, glycogen and digestion — but it is a useful planning figure for setting weight loss calories with this calculator.
How this calorie deficit calculator works
The calculator uses a two-step method that mirrors how dietitians estimate calorie needs:
Step 1: Estimate your maintenance calories (TDEE)
It first calculates your BMR — the calories your body burns at complete rest — using the Mifflin-St Jeor equation: 10 × weight (kg) + 6.25 × height (cm) − 5 × age, plus 5 for men or minus 161 for women. Then it multiplies BMR by an activity factor (1.2 sedentary up to 1.725 very active) to estimate your Total Daily Energy Expenditure. This is the same approach used in our BMR Calculator and TDEE Calculator, so results are consistent across tools.
Step 2: Subtract your chosen deficit
The calculator subtracts 250, 500 or 750 calories from maintenance depending on the pace you select. It also applies a commonly used educational floor — about 1,200 calories per day for women and 1,500 for men — because very low intakes make it difficult to meet protein, vitamin and mineral needs without supervision.
How many calories should you eat to lose weight?
For most adults, the answer is: your maintenance calories minus 250 to 750. A moderately active 30-year-old man of 80 kg and 175 cm has a maintenance level of roughly 2,700 calories, so a standard weight-loss target for him is around 2,200 calories per day. A lightly active 28-year-old woman of 65 kg and 160 cm maintains at roughly 1,850 calories, giving a target near 1,600 with a gentle deficit. Your own numbers depend on your body and routine — which is exactly what the calculator above personalises.
Choosing a safe, sustainable deficit size
Gentle (−250 kcal, ~0.25 kg/week): Best if you are close to your goal weight, new to tracking, or want minimal disruption to energy, training and social meals. Slower on the scale but easiest to keep going for months.
Standard (−500 kcal, ~0.5 kg/week): The most common recommendation and a solid default for most people with 5–20 kg to lose. Noticeable progress with manageable hunger for most people.
Aggressive (−750 kcal, ~0.75 kg/week): Faster, but hunger, fatigue and muscle-loss risk rise. Pair it with a higher protein intake — the Protein Calculator gives a personal gram target — and resistance training, and avoid staying here for long stretches.
Maintenance calories are the starting line
Everything in a calorie deficit plan is anchored to maintenance calories, so a wrong maintenance estimate makes the whole plan wrong. The two biggest sources of error are activity level (most people overestimate it — if unsure, pick the lower option) and body-weight changes (as you lose weight, maintenance falls too). Recalculate every 5–8 kg of loss so your deficit stays real rather than shrinking silently. If you also want context on where your weight sits relative to height, the BMI Calculator is a quick companion check, and the Body Fat Percentage Calculator estimates how much of your weight is fat versus lean mass — useful for judging whether weight loss is coming from the right place.
A worked example
Sara is 35, weighs 72 kg, is 163 cm tall and exercises three times a week (moderate activity). Her BMR works out to about 1,403 calories, and multiplying by 1.55 gives a maintenance level of roughly 2,170 calories. Choosing the standard pace, her daily calorie target is about 1,670 calories, which should produce close to 0.5 kg of loss per week. She sets a protein target of about 115 g per day, plans meals with the Meal Planner, and checks portion calories against the Food Calories Database when logging desi staples like roti, daal and chai.
Making the deficit easier with food swaps
A deficit does not require special foods — it requires that everyday choices add up below your target. Swapping calorie-dense items for lighter equivalents is often the easiest lever: our Food Compare tool and the full Food Comparisons library show these trade-offs side by side. Popular ones for weight loss include Roti vs Bread, Ghee vs Oil, Oats vs Cornflakes, Dates vs Sugar and Paneer vs Chicken. A handful of smart swaps can create 200–400 calories of room per day without shrinking your plate.
Common mistakes in a calorie deficit
Judging progress daily instead of weekly. Water, salt, carbs and hormones swing daily weight by a kilogram or more. Compare weekly averages, not single mornings.
Untracked extras. Cooking oil, chai with sugar, sauces and "just a bite" snacks routinely add 300+ hidden calories. Log them for a week — the pattern is usually obvious.
Cutting protein along with calories. Keeping protein high (roughly 1.4–1.8 g per kg of body weight) protects muscle and keeps you fuller, which makes the deficit sustainable.
Never taking a break. After 8–12 weeks in a deficit, spending one or two weeks eating at maintenance can help with energy, adherence and training quality before you continue.
FAQs: calorie deficit calculator
What is a good calorie deficit for weight loss?
For most people, a deficit of 250-500 calories per day below maintenance is a sustainable starting point, producing roughly 0.25-0.5 kg of weight loss per week. Larger deficits work faster but are harder to sustain and increase the risk of muscle loss and low energy.
How do I calculate my calorie deficit?
First estimate your maintenance calories (TDEE) from your age, sex, weight, height and activity level, then subtract 250-750 calories from that number. This calculator does both steps: it estimates your TDEE using the Mifflin-St Jeor equation and an activity multiplier, then applies the deficit size you choose.
Is a 500 calorie deficit safe?
A 500 calorie daily deficit is a common and generally reasonable target for many adults, producing around 0.5 kg of loss per week. It becomes less appropriate if it pushes total intake very low - as a general educational guideline, most adults should not eat below roughly 1,200 (women) or 1,500 (men) calories per day without professional supervision.
Why am I not losing weight in a calorie deficit?
The most common reasons are underestimating food intake, overestimating activity level, and normal water-weight fluctuations masking fat loss over short periods. Track intake carefully for 2-3 weeks, weigh at the same time of day, and compare weekly averages rather than daily readings before changing your target.
Should I eat back the calories I burn from exercise?
If you selected an activity level that already includes your workouts, no - eating back exercise calories would double-count them. Only add calories back if you chose a sedentary multiplier and then did substantial unplanned activity, and even then fitness trackers often overestimate calories burned.
How many calories should I eat to maintain my weight after losing it?
Recalculate your maintenance calories at your new, lower body weight - it will be lower than when you started. Eating at that updated TDEE keeps weight roughly stable. Recalculate every 5-8 kg of weight change or whenever your activity level changes.
Related tools and pages
General nutrition education only. Not medical advice. If you have a medical condition, are pregnant, or have a history of disordered eating, speak to a qualified professional before changing your diet.