TDEE & calorie deficit calculator
Find your TDEE, then a daily calorie target to lose about a pound a week.
Enter your details above to see your estimate.
These numbers are estimates for healthy adults and aren't medical advice. If you're pregnant or nursing, under 18, or managing a health condition, talk to your doctor before changing how you eat.
How this calculator works
It estimates your BMR (the calories your body burns at rest) with the Mifflin-St Jeor equation — the formula most dietitians use — then multiplies by how active you are to get your TDEE: roughly everything you burn in a day. Subtract a slice of that and you've got a calorie target to lose fat. That's the whole game — fat loss comes from eating a bit less than you burn, repeated consistently. Not keto, not a cleanse. Just the math, made easy to live with.
How big a deficit?
We default to cutting 15–25% off your TDEE — aggressive enough to see real progress, gentle enough that you're not starving or setting up the binge that erases the week. For most people that's a few hundred calories a day and lands you near 0.5–1% of your bodyweight lost per week — about a pound. Faster than that and you start trading away muscle and sanity for a scale number that won't stay.
One honest caveat
This number is an educated guess, not a verdict. Eat at it for 2–3 weeks and watch the trend. Losing too fast and feeling wrecked? Eat a bit more. Nothing moving after three honest weeks? Trim a little. Your real maintenance shows up in the data, not the calculator.
Common questions
How accurate is a TDEE calculator?
It's a solid starting estimate, not a measurement — formulas like Mifflin-St Jeor get most people within a couple hundred calories. Use it to set a target, then adjust based on 2–3 weeks of real-world results.
What's a safe calorie deficit?
For most people, 15–25% below maintenance — roughly 0.5–1% of bodyweight lost per week. Bigger isn't better; steep deficits cost you muscle and rarely last.
Keep reading
Got your number? Now make it stick.
A target you can't see is a target you'll quietly miss — under-logging is the single biggest reason people swear they're in a deficit when they're not. In OgamicX, snap a photo and MealScan estimates the calories, or log it by hand — and every meal fills a daily bar against this exact target. Free to start, no card needed.