Caloric Deficit/Surplus Calculator

Plan your daily calorie target for weight loss or gain. Enter your details and goal to calculate a safe deficit or surplus, see projected weekly change, and estimate how long it will take to reach your goal weight.

Sex
Biological sex
Age
yrs
Units
Unit system
Height
ft
in
Current Weight
lbs
Activity Level
Goal
Weight goal
Rate of Change
Weekly rate of change
Goal Weight (optional)
lbs
How is this calculated?

This calculator uses the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR), which is then multiplied by an activity factor to determine your Total Daily Energy Expenditure (TDEE).

Mifflin-St Jeor BMR:

Male: BMR = (10 × weightkg) + (6.25 × heightcm) − (5 × age) + 5

Female: BMR = (10 × weightkg) + (6.25 × heightcm) − (5 × age) − 161

TDEE = BMR × Activity Multiplier

Caloric adjustment: One pound of body fat is approximately 3,500 calories. To lose or gain weight at a specific rate, a daily caloric deficit or surplus is applied:

0.5 lb/week = 250 cal/day  |  1.0 lb/week = 500 cal/day  |  1.5 lb/week = 750 cal/day  |  2.0 lb/week = 1,000 cal/day

Safety floor: Target calories are never set below 1,200 cal/day for women or 1,500 cal/day for men. If the calculated target falls below these thresholds, a warning is displayed recommending a slower rate of change or consultation with a healthcare provider.

These are estimates. Individual metabolism varies based on genetics, body composition, hormones, and other factors. Use the results as a starting point and adjust based on real-world progress over 2–4 weeks.