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Calorie Calculator

Find how many calories a day to eat to maintain, lose or gain weight, with BMR and TDEE shown, Mifflin-St Jeor by default, and warnings if the target is too low.

Calorie Calculator: with the default inputs, daily calories for your goal is 1,823.

years
ft
in
Try an example
Daily calories for your goal
1,823
Maintenance calories (TDEE)
2,323
Basal metabolic rate (BMR)
1,690
Daily change from maintenance
-500
Weekly change
-3,500
Assumptions
  • BMR from Mifflin-St Jeor unless another formula is selected; activity multipliers 1.2–1.9 are the conventional Harris-Benedict factors.
  • 1 lb of body-weight change ≈ 3,500 kcal (Wishnofsky). Real-world loss slows as maintenance falls.
  • Minimum-intake warnings use 1,200 kcal (women) and 1,500 kcal (men), the usual thresholds for unsupervised dieting.
  • Not intended for children, pregnancy, breastfeeding or anyone under medical care for an eating disorder or metabolic condition.
Daily calories by goal
01,0002,000Maintain weightLose 0.5 lb (0.25 kg)/wkLose 1 lb (0.5 kg)/wkLose 2 lb (1 kg)/wkGain 0.5 lb (0.25 kg)/wkGain 1 lb (0.5 kg)/wk
kcal/day
Calories for each goal
GoalCalories/dayvs. maintenance
Maintain weight2,3230
Lose 0.5 lb (0.25 kg) per week2,073-250
Lose 1 lb (0.5 kg) per week1,823-500
Lose 2 lb (1 kg) per week1,323-1,000Below safe minimum
Gain 0.5 lb (0.25 kg) per week2,573250
Gain 1 lb (0.5 kg) per week2,823500
Math verified by automated testsUpdated 2026-09-083 sources cited

How this is worked out

The formula

BMR (Mifflin-St Jeor) = 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5 (men) or − 161 (women)
TDEE = BMR × activity factor (1.2 sedentary … 1.9 extra active)
Goal calories = TDEE − 500 × (pounds to lose per week)

1 lb of body fat ≈ 3,500 kcal, so 500 kcal/day ≈ 1 lb/week

Open How it’s calculated above to see this worked through with your own numbers.

What you enter

Age
A number.from 15 to 100 · whole numbers only · defaults to 35
Sex
The equations were fitted separately by sex; pick the one that matches your physiology.Male · Female
Height
A number.in ft, in, cm, m · from 2 to 9 · defaults to 5.8333
Weight
A number.in lb, kg, st · from 20 to 1500 · defaults to 165
Activity level
Count planned exercise only; most people overestimate. When in doubt pick one level lower.Sedentary — desk job, little or no exercise (×1.2) · Lightly active — light exercise 1–3 days/week (×1.375) · Moderately active — moderate exercise 3–5 days/week (×1.55) · Very active — hard exercise 6–7 days/week (×1.725) · Extra active — hard daily training plus a physical job (×1.9)
Goal
Choose one of 6 options.Maintain weight · Lose 0.5 lb (0.25 kg) per week · Lose 1 lb (0.5 kg) per week · Lose 2 lb (1 kg) per week · Gain 0.5 lb (0.25 kg) per week · Gain 1 lb (0.5 kg) per week
Formula(under More options)
Choose one of 3 options.Mifflin-St Jeor (recommended) · Harris-Benedict (revised 1984) · Katch-McArdle (needs body fat %)
Body fat(under More options)
Leave at 0 if unknown. Only Katch-McArdle uses it; estimate it with the body fat calculator.a percentage · from 0 to 70 · defaults to 0

What you get back

Daily calories for your goalmain answer
Maintenance calories (TDEE)
What you burn in a typical day at your activity level.
Basal metabolic rate (BMR)
Daily change from maintenance
Negative is a deficit, positive a surplus.
Weekly change
Daily change × 7.

What this assumes

  • BMR from Mifflin-St Jeor unless another formula is selected; activity multipliers 1.2–1.9 are the conventional Harris-Benedict factors.
  • 1 lb of body-weight change ≈ 3,500 kcal (Wishnofsky). Real-world loss slows as maintenance falls.
  • Minimum-intake warnings use 1,200 kcal (women) and 1,500 kcal (men), the usual thresholds for unsupervised dieting.
  • Not intended for children, pregnancy, breastfeeding or anyone under medical care for an eating disorder or metabolic condition.

About this calculator

This calculator estimates how much you burn in a day and then adjusts it for the rate you want to gain or lose. It's the same arithmetic a dietitian would start with — resting metabolism from the Mifflin-St Jeor equation, scaled for activity, then shifted by a deficit or surplus — and every step is shown so you can check it.

How to use it

Enter age, sex, height and weight, pick the activity level that honestly describes a normal week, and choose a goal. Under More options you can switch to Harris-Benedict or, if you know your body fat percentage, Katch-McArdle, which estimates from lean mass and is more accurate for very lean or very muscular people.

The activity level is where most estimates go wrong. Three gym sessions a week on top of a desk job is "lightly active", not "moderately active". If your weight isn't moving the way the number predicts after three or four weeks, adjust by 100–200 kcal rather than second-guessing the formula.

Reading the results

  • Maintenance (TDEE) is what you burn on an average day. Eat this and your weight holds.
  • Your goal calories subtract or add 250–1,000 kcal a day, using the convention that a pound of fat stores about 3,500 kcal. That rule is a simplification — as you lose weight your maintenance falls too, so real loss slows over months (the NIH Body Weight Planner models this dynamically) — but it's the right size for setting a starting target.
  • The table shows every goal at once so you can see what a gentler or faster pace costs.

Warnings worth taking seriously

The calculator flags targets below 1,200 kcal (women) or 1,500 kcal (men). Below those levels it's hard to meet protein and micronutrient needs and guidelines call for medical supervision. It also flags a target below your BMR — a deficit that large tends to cost muscle, not just fat. A 1 lb-per-week deficit with 1.6–2.2 g of protein per kg and some resistance training is the boring, well-supported answer for most people.

What this can't see

Prediction equations are typically within 10% for about seven people in ten. Thyroid function, medications, recent dieting, sleep and how much you fidget all move the true figure. Treat the output as a calibrated starting point, log your intake for a couple of weeks, and let the scale trend correct it.

Frequently asked questions

How many calories should I eat to lose weight?

Subtract 500 kcal a day from your maintenance (TDEE) for roughly a pound a week. Don't go below 1,200 kcal (women) or 1,500 kcal (men) without medical supervision, and don't drop below your BMR for long.

Is the 3,500-calories-per-pound rule accurate?

It's a fair approximation over a few weeks. Over months it overstates loss, because your maintenance falls as you get lighter and your body adapts. Expect loss to slow and re-run the calculator every 10 lb or so.

Why does the calculator say my target is below BMR?

Because the deficit you picked is bigger than the gap between your maintenance and your resting metabolism. That's common for smaller or sedentary people choosing 2 lb a week. Pick a slower rate or add activity to raise maintenance.

Which activity level should I choose?

Base it on planned exercise, not on feeling busy. A desk job with no exercise is sedentary; 1–3 light sessions a week is lightly active; 3–5 real workouts is moderately active. Very and extra active are for daily hard training or physical jobs.

Should I eat back exercise calories?

Not if you already picked an activity level that includes that exercise — you'd be counting it twice. Fitness-tracker calorie burns are also often 20–40% too high.

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