Calorie Calculator – Find Your Daily Calorie Intake
Calculate your calories per day based on your body stats and activity level. Get maintenance calories plus targets for weight loss or muscle gain.
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Mifflin-St Jeor equation
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What is a Calorie Calculator and How Does It Work?
A calorie calculator estimates how many calories you need to eat each day based on your body stats and activity level. Your daily calorie intake is the single most important variable for managing body weight — whether your goal is fat loss, muscle gain, or maintaining where you are. This calculator removes the guesswork by giving you a precise, personalised number.
Anyone who wants to manage their physique effectively should know their calorie needs. Personal trainers designing client nutrition plans, athletes managing performance nutrition, and anyone who has tried generic "eat 1,500 calories" advice and found it ineffective will benefit from a properly calculated, individualised target. Your calorie needs depend on your unique combination of age, gender, height, weight, and daily activity — no single number fits everyone.
This calculator uses the Mifflin-St Jeor equation — the most accurate formula for estimating calorie needs in modern populations — to first calculate your BMR (Basal Metabolic Rate), then multiplies it by your activity level to determine your maintenance calories. From there, it adjusts based on whether you want to lose fat, gain muscle, or maintain your current weight.
Treat your result as a calibrated starting point. Track your intake against this target for 2–3 weeks and monitor your weight trend. If you are not progressing as expected, adjust by 100–200 calories and reassess. Calorie needs are dynamic — they change as your weight, muscle mass, and activity level change — so recalculate every 8–12 weeks for best accuracy.
How to Use This Calorie Calculator
- Select your unit system (metric or imperial) and enter your age, sex, weight, and height.
- Choose your activity level that reflects your average weekly activity — be honest rather than optimistic.
- Select your goal: Lose Weight, Maintain, or Gain Muscle.
- If losing or gaining, choose a weekly target pace — we recommend 0.5 kg/week for most people.
- Click "Calculate My Calories" to see your BMR, TDEE, and personalised daily calorie target.
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What This Calorie Calculator Does
This calorie calculator uses the Mifflin-St Jeor equation—one of the most accurate formulas for estimating your daily calorie intake. It calculates:
BMR
Basal Metabolic Rate
Calories your body burns at complete rest
TDEE
Total Daily Energy
Your maintenance calories including all activity
Goal Calories
Personalized Target
Adjusted for weight loss, maintenance, or muscle gain
How Many Calories Should I Eat Per Day?
Your calories per day depends on three key factors:
Your BMR
Calories your body uses at rest (breathing, circulation, cell repair)
Your Activity & Training
This creates your TDEE (maintenance calories)
Your Goal
Fat loss requires a deficit, muscle gain requires a surplus
📊 Quick reference: Most adults need between 1,600–3,000 calories per day, but this varies significantly based on size, age, sex, and activity level.
Calorie Deficit for Fat Loss
If your goal is weight loss, you need to eat fewer calories than you burn—this is called a calorie deficit. Most people do well with a 10-20% deficit below their TDEE.
💡 Pro Tip
If performance drops or adherence becomes difficult, reduce your deficit slightly and focus on consistency. A smaller deficit you can stick to beats an aggressive one you can't maintain.
What to Do After Using This Calculator
Verify your TDEE
We show it automatically here, but you can also use our TDEE Calculator for more detail
TDEE CalculatorTrack weekly averages
Weight fluctuates daily—focus on 7-day trends, not daily perfection
Adjust based on results
If you're not seeing expected changes after 2-3 weeks, adjust by 100-200 calories
Common Mistakes When Counting Calories
Not tracking consistently
Weekends count. One uncounted day can wipe out a week's deficit.
Underestimating portions
Use a food scale for accuracy, especially for calorie-dense foods like oils, nuts, and cheese.
Overestimating activity
Be honest about your activity level. Most people are "lightly active" even if they exercise.
Expecting linear progress
Weight loss isn't linear. Water retention, hormones, and food volume cause daily fluctuations.
Cutting too aggressively
Extreme deficits lead to muscle loss, metabolic slowdown, and binge eating.
Frequently Asked Questions
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