Loading Calculator...
Please wait a moment
Please wait a moment
Calculate your goal weight, timeline, and calorie deficit needed for safe weight loss
0.5-1 kg per week is safe and sustainable for most people
Daily deficit through diet and exercise combined
Women: 1200+, Men: 1500+ calories per day minimum
BMI-based weight loss planning uses Body Mass Index targets to establish healthy goal weights based on height. Rather than choosing arbitrary numbers, this approach ensures your goal weight falls within medically recommended ranges for optimal health. The BMI weight loss calculator determines how much weight you need to lose to reach a specific BMI or category (underweight, normal, overweight, obese), then estimates the timeline and calorie deficit required using safe weight loss guidelines. Medical professionals recommend losing 1-2 pounds per week, which requires a daily calorie deficit of 500-1000 calories through combined diet and exercise modifications. This gradual approach helps preserve muscle mass, maintains metabolism, and establishes sustainable habits rather than quick fixes that often lead to regain. The calculator accounts for your height to determine appropriate goal weights—what's healthy for someone 5'2" differs significantly from someone 6'0". By targeting a specific BMI within the healthy range (18.5-24.9), you work toward a medically sound weight that reduces disease risk and promotes overall wellness.
Current BMI = weight (kg) / [height (m)]²
Goal Weight (kg) = Goal BMI × [height (m)]²
Example: For height 1.70m and goal BMI of 22: Goal Weight = 22 × (1.70)² = 63.6 kg (140 lbs)
Weight to Lose = Current Weight - Goal Weight
Weeks Needed = Weight to Lose / Safe Weekly Loss Rate (1-2 lbs or 0.5-1 kg)
Example: To lose 30 lbs at 1.5 lbs/week: 30 / 1.5 = 20 weeks (5 months)
One pound of fat = 3,500 calories. To lose 1 lb/week, create 500 calorie daily deficit.
Daily Deficit = (Weekly Weight Loss Goal × 3,500) / 7 days
| Weight to Lose | Timeline (1.5 lbs/week) | Daily Calorie Deficit | Strategy Focus |
|---|---|---|---|
| 10-15 lbs | 7-10 weeks | 500-750 cal | Diet adjustments, light cardio |
| 20-30 lbs | 13-20 weeks | 750 cal | Balanced diet, regular exercise |
| 40-50 lbs | 27-33 weeks | 750-1000 cal | Comprehensive lifestyle change |
| 60+ lbs | 40+ weeks | 1000 cal | Medical supervision recommended |
Combine diet and exercise for best results:
You don't need to reach your ideal BMI immediately to see health benefits. Losing just 5-10% of your body weight (10-20 pounds for someone weighing 200 lbs) can significantly improve health markers including blood pressure, cholesterol, blood sugar, and inflammation. Focus on progress, not perfection, and celebrate small victories along your journey.
While it's possible to lose weight faster initially (especially in the first week due to water weight), sustaining rates above 2 lbs/week often leads to muscle loss, metabolic slowdown, nutrient deficiencies, and difficulty maintaining the loss. Rapid weight loss rarely teaches sustainable habits. Slower, steady loss is more likely to be permanent.
Most people should aim for a BMI in the normal range (18.5-24.9). Within this range, BMI of 22-23 is often considered optimal for longevity. However, your ideal BMI depends on factors like muscle mass, age, ethnicity, and overall health. Consult healthcare providers for personalized recommendations. Don't aim for the lowest possible BMI—mid-range is usually healthiest.
Combine diet and exercise. Examples: Skip 200 calories of snacks + 45-minute brisk walk (300 cal) = 500 deficit. Or reduce portions at meals (-300 cal) + 30 minutes cycling (200 cal) = 500 deficit. Mix strategies for sustainability. Don't cut calories too drastically, as this slows metabolism and is hard to maintain.
Plateaus are normal. As you lose weight, your body requires fewer calories, so your initial deficit shrinks. Additionally, metabolic adaptation can occur. To overcome plateaus: recalculate your calorie needs at your new weight, increase exercise intensity or duration, ensure accurate food tracking, manage stress and sleep, and be patient—plateaus often break after 2-4 weeks.
No, women should not regularly eat below 1200 calories and men below 1500 calories without medical supervision. Very low calorie diets risk nutrient deficiencies, muscle loss, fatigue, and metabolic slowdown. They're also unsustainable. If calculated deficit requires eating below these minimums, increase exercise rather than further reducing food intake, or accept slower weight loss.
While weight loss primarily comes from calorie deficit (diet), exercise is crucial for: preserving muscle mass during weight loss, improving body composition, boosting mood and energy, increasing calorie burn, and maintaining loss long-term. Combine cardio (burns calories) with strength training (preserves/builds muscle). Exercise makes weight maintenance much easier after reaching your goal.
For significant weight loss (50+ pounds), consider working with healthcare professionals including doctors, registered dietitians, and possibly therapists. Medical supervision helps ensure safety and addresses underlying health conditions. Break your goal into smaller milestones (10-15 lbs at a time) to stay motivated. Remember that even partial progress delivers health benefits—you don't have to reach ideal BMI immediately.
Maintenance requires ongoing attention. Calculate your maintenance calories (no deficit), continue tracking food intake, maintain regular exercise, weigh yourself weekly to catch small gains early, keep healthy eating habits you developed during weight loss, allow occasional treats in moderation, and stay connected to supportive communities. Most people who maintain loss continue monitoring and exercising regularly.
This BMI weight loss calculator is provided for informational and educational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Weight loss recommendations are general guidelines that may not be appropriate for everyone. Individual calorie needs, safe weight loss rates, and goal weights vary based on age, gender, activity level, medical conditions, medications, and other factors. Before beginning any weight loss program, especially if you have significant weight to lose or existing health conditions, consult with qualified healthcare providers including physicians and registered dietitians. They can provide personalized guidance, monitor your progress safely, and adjust recommendations based on your unique situation. Very low calorie diets, rapid weight loss, and extreme exercise should only be undertaken with medical supervision. The timeline and calorie estimates provided are approximations—actual results will vary. Never eat below recommended minimum calorie levels (1200 for women, 1500 for men) without medical supervision. If you experience unusual symptoms, excessive fatigue, or health concerns during weight loss, seek medical attention immediately.