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Calorie Calculator.

Calculate daily calorie needs for weight goals

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Daily Energy Expenditure

This calculator estimates how many calories your body uses in a day, based on your size, age, and how active you are. Use it as a starting point for planning your intake.

Your Daily Calorie Needs

BMR

1649 cal/day

Calories burned at complete rest

TDEE

2556 cal/day

Calories burned including activity

Calorie Targets by Goal

Weight loss

Mild loss2300
Moderate loss2044
Extreme loss1533

Weight gain

Mild gain2811
Moderate gain3067
Fast gain3322
Maintenance2556 cal/day
Weekly loss at moderate deficit: 0.45 kg

Weekly loss at moderate deficit

0.45 kg
Monthly loss at moderate deficit: 1.8 kg

Monthly loss at moderate deficit

1.8 kg
Calories per kg of body weight: 37

Calories per kg of body weight

37.00

Important Notes

  • These figures are estimates; your real needs may differ by 10% or more.
  • Track your weight and intake for a few weeks, then adjust to what you see.
  • Very low intakes can leave you short on nutrients — check with a professional first.
  • Resistance training helps you keep muscle while losing weight.
  • Stay hydrated; thirst is easily mistaken for hunger.

How to Use the Calorie Calculator

The calculator works out your basal metabolic rate and scales it by your activity level to estimate daily calorie needs.

  1. Enter your age and gender. Both affect your metabolic rate, so accurate values give a closer estimate.
  2. Add your weight and height. Switch between metric and imperial units to match how you normally measure.
  3. Pick your activity level. Choose the option that matches a typical week, not your best week.
  4. Choose a target. Use the maintenance figure to hold your weight, or a loss or gain target to change it.

Understanding BMR and TDEE

Basal metabolic rate (BMR) is the energy your body uses at complete rest to run essential functions like breathing, circulation, and cell repair. It typically accounts for most of the calories you burn in a day.

Total daily energy expenditure (TDEE) is your BMR plus everything else: walking, working, exercising, and digesting food. This is the number to compare against your intake when planning a goal.

This calculator uses the Mifflin-St Jeor equation, which is widely regarded as one of the more accurate predictive formulas for healthy adults. It remains an estimate — individual metabolism varies.

Calories and Weight Change

Weight changes when your intake differs from what you burn over time. A deficit of roughly 500 calories a day tends to produce around 0.45 kg (1 lb) of loss per week, though the rate slows as you get lighter.

Practical Tips

  • Aim for a moderate deficit. Smaller deficits are easier to sustain and tend to preserve more muscle than aggressive ones.
  • Prioritise protein. Protein keeps you fuller for longer and helps protect lean mass while you lose weight.
  • Weigh your food at first. Portion estimates drift over time; a few weeks of weighing recalibrates them.
  • Keep lifting. Resistance training signals your body to hold on to muscle during a deficit.
  • Expect fluctuations. Water, salt, and digestion move the scale daily — judge progress by weekly averages.
  • Recalculate as you go. Your needs fall as your weight does, so update your target every few kilograms.

Activity Level Guidelines

Sedentary

A desk job and little deliberate exercise. Most of the day is spent sitting.

Lightly active

Light exercise or sport one to three days a week, or a job with some walking.

Moderately active

Moderate exercise three to five days a week, such as regular gym sessions or team sport.

Very active

Hard exercise six to seven days a week, or training on most days.

Extra active

Hard daily training plus a physically demanding job, or twice-daily sessions.

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FAQs

How many calories should I eat per day?

Daily calorie needs vary by age, gender, weight, height, and activity level. On average, adult women need 1,600-2,400 calories and men need 2,000-3,000 calories. Use our calculator for personalized recommendations.

What is the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the calories your body burns at rest. TDEE (Total Daily Energy Expenditure) is your BMR plus calories burned through activity. TDEE represents your total daily calorie needs.

How many calories should I eat to lose weight?

For safe weight loss, create a calorie deficit of 500-750 calories per day, which typically results in 1-1.5 pounds of weight loss per week. Never go below 1,200 calories (women) or 1,500 calories (men) without medical supervision.

Does the calculator account for exercise?

Yes, our calculator includes activity level factors ranging from sedentary to very active. Your TDEE calculation incorporates your exercise habits to provide accurate calorie recommendations.

Cite this calculator

Canonical URL: https://mathify.one/zh/fitness/calorie

Cite as: Mathify. (2026). 卡路里计算器. https://mathify.one/zh/fitness/calorie

Use Cases

Weight Management Planning

Determine your daily calorie needs to create a plan for losing, gaining, or maintaining weight.

Example: Find your maintenance calories, then subtract 500 to aim for about 1 lb loss per week.

Fitness Goal Setting

Set a daily calorie target that aligns with your fitness objectives, whether you're training for an event or building muscle.

Example: If you're active and want to gain muscle, set a target above your estimated burn.

Frequently Asked Questions

How does the calorie calculator estimate daily burn?
It uses your personal details and activity level to estimate your total daily energy expenditure (TDEE), which is the number of calories you burn per day.
Can I use this calculator to lose weight?
Yes, you can set a target based on your goal. For weight loss, a common approach is to create a calorie deficit by eating fewer calories than your estimated burn.
Is this calculator accurate?
It provides an estimate based on standard formulas. Individual metabolism varies, so use it as a starting point and adjust based on your results.

Tips & Common Mistakes

Tips

  • Be honest about your activity level to get a more accurate estimate.
  • Recalculate your calorie needs as your weight changes.
  • Use the target as a guideline, not a strict rule, and listen to your body.
  • Combine with a balanced diet and regular exercise for best results.

Common Mistakes to Avoid

  • Overestimating activity level, which can lead to a higher calorie target than needed.
  • Setting an extreme calorie deficit that is unsustainable and unhealthy.
  • Ignoring the difference between total calories and macronutrient quality.

Last updated: August 13, 2026