Calorie Calculator

How this calorie calculator works

Enter your sex, age, height, weight, and activity level to get your Basal Metabolic Rate (BMR), your Total Daily Energy Expenditure (TDEE, or maintenance calories), and a daily calorie target based on your goal of losing, maintaining, or gaining weight.

The calorie formula (Mifflin-St Jeor)

This calculator uses the Mifflin-St Jeor equation, widely regarded as the most accurate BMR formula for the general population:

Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) + 5
Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age(years) − 161

TDEE = BMR × activity multiplier (ranging from 1.2 for sedentary to 1.9 for very active).

Step-by-step: how to calculate your calorie needs

Calculate your BMR using the formula for your sex.
Multiply your BMR by your activity level multiplier to get your TDEE (maintenance calories).
Subtract roughly 500 calories per day from TDEE to lose about 1 pound per week, or add roughly 500 to gain about 1 pound per week.
Adjust gradually over a few weeks based on your actual results, since individual metabolism varies from formula estimates.

Worked example

A 30-year-old man, 170 cm tall, weighing 70 kg, with moderate activity (exercising 3-5 days a week):

BMR = 10×70 + 6.25×170 − 5×30 + 5 = 700 + 1062.5 − 150 + 5 = 1,618 calories/day
TDEE = 1,618 × 1.55 (moderate activity) = ≈ 2,507 calories/day
To lose about 1 lb/week: 2,507 − 500 = ≈ 2,007 calories/day

Common calorie calculation mistakes

Overestimating activity level. Most people who aren’t training regularly fall into the sedentary or light category, not moderate or active.
Cutting calories too aggressively. A large deficit can slow your metabolism and is harder to sustain long-term.
Not adjusting over time. As you lose or gain weight, your BMR changes, so your target should be recalculated periodically.
Ignoring protein and nutrient quality while focusing only on the total calorie number.

Tips for reaching your calorie goal

Track your actual weight change over 2-3 weeks and adjust your target if progress stalls or moves too fast.
Prioritize protein intake to help preserve muscle mass during a calorie deficit.
A moderate deficit or surplus of 300-500 calories per day is generally more sustainable than an aggressive one.
Recalculate your BMR and TDEE every 10-15 lbs of weight change, since your calorie needs shift as your body changes.

What’s the difference between BMR and TDEE?

BMR is the energy your body needs at complete rest just to function. TDEE adds your daily activity on top of BMR, giving you the total calories you burn in an average day, which is the number you should compare against your food intake.

How many calories should I eat to lose weight?

A common approach is eating roughly 500 calories below your TDEE per day, which corresponds to about 1 pound of weight loss per week, though individual results vary and very low intakes below 1,200-1,500 calories generally aren’t recommended without medical supervision.

Is the Mifflin-St Jeor formula accurate?

It’s one of the most accurate BMR formulas for the general population, validated in multiple studies, though any formula is an estimate and actual metabolism varies between individuals by up to 10-15%.

Should I recalculate my calories as I lose weight?

Yes. As your weight decreases, your BMR and TDEE decrease too, so recalculating every 10-15 pounds keeps your calorie target accurate.