It estimates BMR with the Mifflin-St Jeor equation, multiplies it by your activity level to estimate maintenance calories, then subtracts a selected daily deficit. For deeper planning, compare it with the official NIH/NIDDK Body Weight Planner.
BMR is the estimated energy your body uses at rest. TDEE, or maintenance calories, adds activity on top of BMR. The WHO physical activity guidance explains why movement changes daily energy needs.
No. A larger deficit can be harder to sustain and may reduce training quality, energy, and adherence. Treat the aggressive plan as a short-term scenario, not a medical prescription.
No. This is an educational estimate for adults. If you have a medical condition, are pregnant, have a history of disordered eating, or plan a large deficit, speak with a qualified clinician.
This calculator turns body metrics into a calorie target using a transparent BMR → maintenance → deficit flow. It pairs well with official tools like the NIH/NIDDK Body Weight Planner when you want a more detailed long-term model.
"A good deficit is the smallest deficit you can repeat consistently while still training, sleeping, and eating enough protein and micronutrients."
Formula
BMR uses the Mifflin-St Jeor equation, a widely cited adult resting energy estimate.
Activity
Activity multipliers are planning assumptions. Adjust after 2-3 weeks of real scale and habit data.
Safety
Avoid treating aggressive cuts as permanent. If symptoms, fatigue, or disordered eating patterns appear, pause and get clinical support.
