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🍽 Daily Calorie Needs

Calorie Calculator

Estimate how many calories you need each day to maintain your weight, and see clear targets to lose or gain weight at a healthy pace — updating live as you type.

📏 Your Details
Age
yrs
1590 yrs
Height
cm
120210 cm
Weight
kg
30180 kg
2,556 kcal/day
Calories to maintain weight
BMR (at rest) ≈ 1,649 kcal/day
🔥 Your Energy Use
2,556
kcal/day to maintain
Resting (BMR) Activity
Illustrative physique — fuel your training with the right daily calories.
BMR (calories at rest)
1,649
kcal / day
Maintenance (TDEE)
2,555
kcal / day at activity level

BMR is the energy you use at complete rest. Maintenance (TDEE) is your BMR scaled by activity — the calories to keep your weight steady. These are estimates, not personal targets.

🎯 Daily Calorie Targets by Goal

Targets apply a calorie deficit (to lose) or surplus (to gain) to your maintenance level — about 7,700 kcal is stored in 1 kg of body fat, so ~500 kcal/day ≈ 0.5 kg/week. Rows below a safe daily minimum are dimmed and flagged. These are general estimates, not a prescription; speak with a doctor or registered dietitian before starting any calorie goal.

How Your Calories Are Calculated

1. BMR (Mifflin–St Jeor) — Men: 10×kg + 6.25×cm − 5×age + 5; Women: use −161 instead of +5.

2. Maintenance calories = BMR × activity factor.

3. Goal calories = maintenance − deficit (lose) or + surplus (gain).

How Many Calories Do You Need a Day?

A calorie is a unit of energy. The calories in food and drink fuel everything your body does, from breathing and circulating blood to walking and exercising. The number you need each day depends on your age, sex, height, weight and how active you are. This calculator estimates your maintenance calories — the amount that keeps your weight stable — by working out your resting metabolism and multiplying it by an activity factor.

As a very rough guide, calorie needs often fall around 2,000 a day for women and 2,500 a day for men, but individual needs vary widely. The figure above is personalised to the details you enter.

Tip: pair this with our BMR Calculator, BMI Calculator and Body Fat Calculator for a fuller picture of your body and energy needs.

Important: These figures are general estimates, not personalised targets or medical advice. Calorie needs vary with body composition, genetics, hormones, health conditions and activity. Talk to a doctor or registered dietitian before changing your diet or setting weight goals, especially if you are pregnant, have a health condition, or have any history of disordered eating.

Calorie Targets for Losing or Gaining Weight

Weight change comes down to energy balance. Eating fewer calories than you burn creates a deficit and leads to weight loss; eating more creates a surplus and leads to weight gain. Because roughly 7,700 calories are stored in a kilogram of body fat (about 3,500 per pound), a daily deficit of around 500 calories produces about half a kilogram of loss per week.

The goal table above turns this into concrete daily numbers. Gentle, gradual changes are easier to sustain and protect muscle and energy levels far better than crash diets.

How low is too low? Most adults should not drop below about 1,200 calories/day for women or 1,500 calories/day for men without medical supervision, and eating below your BMR for long stretches is best avoided. Very low intakes risk fatigue, nutrient gaps and muscle loss. Any target flagged below the safe minimum in the table should only be considered with professional guidance.

How Calorie Counting Works

Calorie counting is a simple feedback loop:

You rarely need to count forever. A few weeks is usually enough to learn the calorie content and portion sizes of your regular meals.

Zigzag Calorie Cycling

Instead of eating the exact same calories every day, zigzag cycling varies your intake across the week while keeping the weekly average on target — for example, slightly more on training days and less on rest days. The idea is to make a plan more flexible and social, and possibly to reduce the body's adaptation to a constant intake. The weekly total is what matters most.

Calories: Energy In vs Energy Out

"Energy in" is the calories you eat and drink; "energy out" is the calories you burn through your resting metabolism, daily movement and exercise. Over time, the balance between the two determines whether you lose, maintain or gain. Calorie quality still matters: whole foods rich in protein and fibre keep you fuller and support health far better than the same calories from highly processed options, even when the totals match.

Calories in Some Common Foods

FoodTypical servingApprox. calories
Apple1 medium95
Banana1 medium105
Egg1 large78
Bread1 slice80
White rice (cooked)1 cup205
Chicken breast (cooked)100 g165
Whole milk1 cup150
Almonds28 g (1 oz)164
Avocado1/2 fruit161
Olive oil1 tbsp119

From Maintenance to Daily Calories (Activity Multipliers)

Activity levelDescriptionMultiplier
SedentaryLittle or no exercise, desk job× 1.2
Lightly activeLight exercise 1–3 days/week× 1.375
Moderately activeModerate exercise 3–5 days/week× 1.55
Very activeHard exercise 6–7 days/week× 1.725
Extra activeVery hard exercise or a physical job× 1.9

Simple Tips for Managing Calories

Frequently Asked Questions

How many calories should I eat to lose weight?

Eat fewer calories than you burn. A sustainable target is a 250–500 calorie daily deficit (about 0.25–0.5 kg or 0.5–1 lb per week). Most adults should stay above ~1,200 (women) or ~1,500 (men) calories per day without medical supervision.

How many calories are in one kilogram of body fat?

About 7,700 calories (roughly 3,500 per pound). That is why a daily deficit of about 500 calories tends to give around half a kilogram of fat loss per week.

Is it safe to eat below my BMR?

Not for extended periods without medical supervision. Very low intake can cause fatigue, nutrient deficiencies and muscle loss. Keep deficits moderate and seek professional advice before any aggressive plan.

How accurate is a calorie calculator?

It is a solid starting estimate from validated equations, but real needs vary. Track your weight over 2–3 weeks and adjust intake up or down based on the actual trend.

What is a calorie deficit?

Eating fewer calories than your body uses in a day, so it draws on stored energy and you lose weight. A surplus is the opposite and leads to gain.

Do I have to count calories forever?

No. Many people count for a few weeks to learn portion sizes and the calorie content of their usual meals, then maintain results with those habits.

Sources & References

Calorie needs are estimated with the Mifflin–St Jeor equation (with Harris–Benedict and Katch–McArdle as options) scaled by activity. For trusted nutrition guidance see the U.S. Dietary Guidelines, the U.S. NIDDK weight-management information and the NHS healthy weight resources. This page is general information, not medical advice.