Calorie Deficit Calculator
Find your maintenance calories and how much to eat each day to lose 0.5 to 2 pounds a week, with a safe calorie floor, the date you'd reach your goal weight, a week-by-week projection and a starting protein, fat and carb split.
Calorie deficit calculator
Starting macro split
How the calorie deficit is calculated
- BMR by the Mifflin-St Jeor equation (see the BMR calculator).
- Maintenance calories (TDEE) = BMR × your activity factor.
- Deficit = pounds per week × 3,500 ÷ 7. One pound a week is about 500 calories a day; two pounds is about 1,000.
- Target = maintenance − deficit, never below 1,200 calories a day for women or 1,500 for men without medical supervision.
Example: a 30-year-old man, 180 lb, 5'10", lightly active: BMR 1,783, maintenance 2,451. To lose 1 lb a week he'd eat about 1,950 calories a day and reach 165 lb in about 15 weeks.
Maintenance calorie calculator, TDEE calculator, calorie intake calculator
Maintenance calories, TDEE and "calories to maintain weight" are the same number: what you burn in a typical day. Eat that and your weight should hold steady. Track your weight for 2 to 3 weeks; if it doesn't move as expected, adjust by 100 to 200 calories, because formulas can be off by about 10% for any one person.
Why the 3,500-calorie rule is only a starting point
As you lose weight you burn fewer calories, so the same deficit produces slower loss over time. The NIH Body Weight Planner models this; for planning, expect the pace to slow after the first few months and recalculate every 10 lb or so. A rate of 0.5 to 2 lb a week (about 1% of body weight) is the usual guidance, with enough protein (about 0.7 to 1 g per pound of goal weight) and strength training to keep muscle.
Macro calculator and protein calculator
Calorie calculator: calories to maintain, lose or gain
As a calorie calculator, the tool at the top gives your maintenance calories; subtract about 500 a day to lose 1 lb a week, or add 250 to 500 to gain slowly.
Protein calculator: protein intake calculator
The protein intake calculator multiplies body weight by a protein target: the RDA minimum is 0.36 g per lb (0.8 g/kg); 0.7 to 1.0 g per lb helps keep muscle while dieting or build it when lifting. At 180 lb and 0.7 g/lb that's 126 g a day (504 calories).
Macro calculator
Protein and fat have 4 and 9 calories per gram; carbohydrate 4. The macro calculator sets protein first, fat as a share of calories, and fills the rest with carbs.
Common questions
How many calories should I eat to lose 1 pound a week?
About 500 fewer than your maintenance calories each day.
What is a safe calorie deficit?
500 to 1,000 calories a day (1 to 2 lb a week) for most adults, staying above 1,200 (women) or 1,500 (men) a day.
How do I calculate maintenance calories?
BMR × activity factor. A lightly active 180 lb, 5'10", 30-year-old man maintains on about 2,450 calories a day.
Why am I not losing weight in a calorie deficit?
Water swings can hide fat loss for 1 to 3 weeks, and intake is easy to underestimate. If nothing changes in 3 weeks, cut 100 to 200 calories or add activity.
Is TDEE the same as maintenance calories?
Yes: total daily energy expenditure is the calories you burn, so eating that maintains your weight.
Sources
- NIH NIDDK: Body Weight Planner
- Hall et al. (2011), Lancet: Quantification of the effect of energy imbalance on bodyweight
- Mifflin et al. (1990), Am J Clin Nutr
Related
General information, not financial, tax or legal advice. Check important numbers with the official source before acting on them.