Calorie Calculator
Estimate how many calories you need each day to maintain or lose weight, using the clinically validated Mifflin-St Jeor formula. Enter your details below.
How the calorie calculator works
This calorie calculator estimates your Total Daily Energy Expenditure (TDEE), the total calories your body burns in a day. It uses the Mifflin-St Jeor equation to find your resting metabolic rate, then multiplies by an activity factor based on how much you move. Eat around your TDEE to maintain weight, below it to lose, and above it to gain.
How many calories should I eat to lose weight?
Sustainable weight loss usually comes from a moderate calorie deficit, not an extreme one. A deficit of about 20 percent below your TDEE supports a steady loss of roughly one to two pounds per week for most people, which the calculator shows alongside your maintenance number. Protein intake, sleep, and consistency matter as much as the number itself.
A note on very low calorie targets: Cutting calories too aggressively can slow your metabolism, cost you muscle, and make a plan hard to sustain. More restriction is not better. If you are unsure what target is right for you, that is a good conversation to have with a provider.
Calories and GLP-1 weight loss
GLP-1 medications like semaglutide and tirzepatide reduce appetite directly, so most patients naturally eat 20 to 40 percent fewer calories without forcing it. That is the medication working as intended. On a GLP-1 program, the focus shifts from strict calorie counting to protein quality and adequate nutrition, so you lose fat while protecting muscle. In trials, semaglutide produced an average 14.9 percent body weight reduction (STEP 1) and tirzepatide an average 20.9 percent reduction (SURMOUNT-1). Individual results vary. See our medical weight loss overview for the full program.
Explore Your Weight Loss Options
Know Your Numbers. Know Your Options.
Your calorie target is a starting point. A free consultation with the Tactus Health team turns it into a plan that fits your body and goals.
Book a Free ConsultationThis calorie calculator is an educational screening tool and does not constitute medical advice, diagnosis, or treatment. Estimates are based on the Mifflin-St Jeor equation and may not reflect your individual metabolic needs. Calorie targets are not appropriate for everyone, and very low intakes can be harmful. Always consult a licensed medical provider before starting any weight loss, diet, or medication program. Individual results vary.