TDEE and Calorie Deficit: A Beginner's Guide With Examples
Use the Mifflin-St Jeor formula to estimate your TDEE, then set a safe calorie deficit (10-25%) for steady, sustainable weight loss without crash dieting.
TDEE and Calorie-Deficit Calculator for Weight Loss
A free, browser-based calculator for estimating your total daily energy expenditure (TDEE) with the Mifflin-St Jeor equation, then setting a sensible calorie deficit of 300–500 kcal per day for steady, sustainable weight loss. The tool runs in your browser — nothing is saved, nothing is sent anywhere.
How to use the TDEE calculator
- Estimate your BMR with Mifflin-St Jeor using your weight, height, age, and sex.
- Multiply by an activity factor (1.2 sedentary, 1.375 lightly active, 1.55 moderately active) to get TDEE. Round down between rows — most adults overestimate their activity by about half a category.
- Subtract 300–500 kcal for a beginner-safe deficit that targets about 0.5–1 lb of weight loss per week while staying above the roughly 1,200 kcal (women) or 1,500 kcal (men) safety floor.
- Reassess every 2–4 weeks against a 7-day rolling weight average. If weight is flat for 3+ weeks of honest tracking, trim another 100–200 kcal or add the same as activity before cutting further.