Overweight Calculator
This calculator is for informational purposes only and is not a substitute for professional medical advice. Consult a healthcare provider for personal health decisions.
BMI categories, healthy range, calorie deficit, and time to goal
How Overweight Assessment Works
This calculator goes beyond basic BMI by quantifying how far you are from a healthy weight range, estimating a calorie plan, and projecting time to goal. It uses standard BMI categories extended to obese Class I (30–34.9), II (35–39.9), and III (≥40), plus underweight below 18.5.
Healthy weight for your height comes from BMI 18.5–24.9: min = 18.5 × height(m)², max = 24.9 × height(m)². If you weigh more than the max, the calculator shows kg and lbs over the upper limit (or under the lower limit if underweight). TDEE uses the Mifflin-St Jeor BMR with your activity level; a default 500 kcal/day deficit targets roughly 0.5 kg (1 lb) loss per week.
Example: BMI 32 at 175 cm might show ~15 kg over the healthy maximum. At a 500 kcal deficit from TDEE, estimated weeks to goal = excess weight ÷ 0.5 kg/week. Health risk text summarizes cardiovascular and metabolic associations by BMI class.
BMI screening has known limits — muscle mass, ethnicity, and age affect interpretation. Use this as a planning starting point alongside medical advice. Pair with the healthy weight and calorie calculators for detailed range and macro planning.
Examples
| Example | Result |
|---|---|
| BMI 27, 175 cm | Overweight category + kg over limit |
| BMI 32 | Obese Class I + deficit plan |
| BMI 17 | Underweight + kg below healthy minimum |
Frequently asked questions
The calculator compares your weight to the BMI 24.9 upper limit (or 18.5 lower limit if underweight) and shows the difference in kg or lbs.
A 500 kcal/day deficit approximates 0.5 kg (1 lb) fat loss per week — a commonly recommended sustainable rate. Minimum intake is capped at 1200 kcal for safety.
WHO subclassifications: Class I BMI 30–34.9, Class II 35–39.9, Class III ≥40. Higher classes correlate with greater health risk.