How Many Calories Do You Need?
Calculate your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) using the scientifically validated Mifflin-St Jeor equation.
Track Your Calories Automatically
Snap a photo of any meal — Indian, Japanese, home-cooked, or restaurant — and get an instant calorie and macro breakdown. No manual logging.
⬇ Download MyBiteIQ FreeWhat is TDEE and why does it matter?
Your TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a day, including everything from breathing to exercise. It's the single most important number for weight management: eat below your TDEE and you lose weight, eat above it and you gain. Everything starts with knowing this number.
What is the Mifflin-St Jeor equation?
The Mifflin-St Jeor equation (1990) is considered the most accurate formula for estimating BMR in the general population, and it's the standard used by registered dietitians. This calculator computes your BMR with it, then multiplies by an activity factor to estimate your TDEE:
- Men: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age + 5
- Women: BMR = 10 × weight(kg) + 6.25 × height(cm) − 5 × age − 161
How many calories to lose weight?
A deficit of about 500 calories a day generally produces roughly 0.5 kg (1 lb) of weight loss per week — sustainable for most people. This calculator shows your “Lose Weight” target as TDEE minus 500 (with a 1,200-calorie floor). To go deeper on deficits, see our guide to calorie deficits.
Why calories aren't the whole story
Knowing your target is step one — hitting it accurately, day after day, is what actually moves the scale. Most people underestimate what they eat by 20–30%. That's exactly the gap MyBiteIQ closes: photo-based logging, a 300K+ food database, and weekly trends so you know your real intake, not a guess. Read why you can't outrun a bad diet.
Also try our BMI calculator to find your healthy weight range.