Reverse BMI Calculator
Planning a diet and wondering what weight to aim for? Our free Reverse BMI Calculator does something most BMI tools can’t — it works backward. Enter your height and your desired BMI (for example, 22), and it instantly tells you the exact weight you need to reach that goal.
No guesswork. No complicated math. Just a clear, science-based number you can plan around.
Reverse BMI Calculator
Find the exact weight or height you need to reach your target BMI goal
What Is a Reverse BMI Calculator?
A reverse BMI calculator is a tool that estimates a person’s target weight given their height and a desired BMI value.
A standard BMI calculator works like this:
You enter weight + height → it gives you BMI.
A reverse BMI calculator flips that equation:
You enter height + target BMI → it gives you weight.
This makes it an invaluable planning tool for anyone who has a BMI goal in mind — whether that’s reaching a “normal” BMI of 22, understanding what weight corresponds to the boundary of “overweight” (BMI 25), or simply exploring the BMI-weight relationship for their body.
Why Would You Need a Reverse BMI Calculator?
Most people know about BMI, but very few know what weight they’d need to be to actually hit a specific BMI number. Here are the most common use cases:
🎯 Diet & Weight-Loss Planning
If your doctor recommends reaching a BMI of 22–24, our calculator tells you the exact weight target in kilograms or pounds — giving your diet plan a concrete finish line.
🏥 Pre-Surgery Requirements
Many bariatric and elective surgeries require patients to reach a specific BMI threshold. A reverse BMI calculator shows you the weight you need to hit.
🏋️ Fitness Goal Setting
Whether you’re bulking or cutting, knowing the weight that corresponds to specific BMI benchmarks helps you set realistic, measurable goals.
📊 Health Curiosity
You might simply want to explore: “What would I weigh at a BMI of 20 versus 25 at my height?” This tool answers that in seconds.
How to Use Our Reverse BMI Calculator
Using the calculator takes less than 30 seconds. Here’s how:
Step 1: Determine Your Height
Measure your height accurately. You can enter it in centimeters (metric) or feet and inches (imperial) — our calculator supports both.
Step 2: Choose Your Target BMI
Use the interactive slider to select your desired BMI value. The calculator highlights which BMI category your target falls into:
| BMI Range | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Normal weight |
| 25.0 – 29.9 | Overweight |
| 30.0 and above | Obese |
Step 3: Click “Calculate Result”
The calculator instantly displays:
- ✅ Your target weight in your chosen unit (kg or lbs)
- ✅ An automatic conversion to the other unit system
- ✅ The healthy weight range (BMI 18.5–24.9) for your height
- ✅ A visual BMI scale showing where your target sits
- ✅ Your BMI category badge (Normal, Overweight, etc.)
The Reverse BMI Formula Explained
The math behind the reverse BMI calculator is straightforward. It’s the standard BMI formula rearranged to solve for weight instead of BMI.
Standard BMI Formula
BMI=Height2Weight
Reverse BMI Formula (Solving for Weight)
Metric (kg and meters):
Weight(kg)=BMI×Height(m)2
Convert centimeters to meters first: divide cm by 100.
Imperial (lbs and inches):
Weight(lbs)=703BMI×Height(in)2
The constant 703 converts the metric BMI formula to work with pounds and inches.
Worked Example
Let’s say you are 175 cm tall and want a BMI of 22:
- Convert height to meters: 175 ÷ 100 = 1.75 m
- Square the height: 1.75 × 1.75 = 3.0625
- Multiply by target BMI: 22 × 3.0625 = 67.4 kg
Result: You would need to weigh approximately 67.4 kg (148.6 lbs) to have a BMI of 22 at 175 cm tall.
Reverse BMI Reference Table
The table below shows the target weight (in kg and lbs) for common heights at three BMI values: 18.5 (lower boundary of normal), 22 (mid-normal), and 25 (upper boundary of normal).
| Height (cm) | Height (ft/in) | Weight at BMI 18.5 | Weight at BMI 22 | Weight at BMI 25 |
|---|---|---|---|---|
| 152 | 5’0″ | 42.7 kg (94 lbs) | 50.8 kg (112 lbs) | 57.8 kg (127 lbs) |
| 157 | 5’2″ | 45.6 kg (100 lbs) | 54.2 kg (120 lbs) | 61.6 kg (136 lbs) |
| 163 | 5’4″ | 49.2 kg (108 lbs) | 58.5 kg (129 lbs) | 66.4 kg (146 lbs) |
| 168 | 5’6″ | 52.2 kg (115 lbs) | 62.1 kg (137 lbs) | 70.6 kg (156 lbs) |
| 173 | 5’8″ | 55.4 kg (122 lbs) | 65.8 kg (145 lbs) | 74.8 kg (165 lbs) |
| 178 | 5’10” | 58.6 kg (129 lbs) | 69.7 kg (154 lbs) | 79.2 kg (175 lbs) |
| 183 | 6’0″ | 62.0 kg (137 lbs) | 73.7 kg (162 lbs) | 83.7 kg (185 lbs) |
| 188 | 6’2″ | 65.4 kg (144 lbs) | 77.7 kg (171 lbs) | 88.4 kg (195 lbs) |
| 193 | 6’4″ | 69.0 kg (152 lbs) | 82.0 kg (181 lbs) | 93.1 kg (205 lbs) |
Frequently Asked Questions
What is BMI?
BMI stands for Body Mass Index. It is calculated as weight in kilograms divided by height in meters squared (kg/m²). BMI is a screening measure of weight category — it indicates whether a person’s weight is in a range that is generally considered healthy for their height. However, BMI does not directly diagnose health or measure body fat percentage.
What is a Reverse BMI?
A reverse BMI is a method for estimating a person’s weight given their BMI and height. It uses the same BMI formula, rearranged to solve for weight instead of BMI.
How do you calculate weight from BMI?
Follow these three steps:
- Determine your height. Measure in inches (for the imperial formula) or convert centimeters to meters (cm ÷ 100) for metric.
- Choose your target BMI. For example, 22 for the middle of the “normal” range.
- Apply the formula. Metric: Weight (kg) = BMI × Height (m)². Imperial: Weight (lbs) = BMI × Height (in)² ÷ 703.
Is Reverse BMI medically accurate?
The formula is mathematically precise — for any given height and BMI, it correctly computes the corresponding weight. However, BMI itself has limitations. It does not account for:
- Muscle mass vs. fat mass
- Bone density
- Age and gender differences
- Ethnic variations in body composition
BMI is a screening tool, not a diagnostic measure. Always interpret results with context.
Can I use this calculator for children or teenagers?
No. This calculator is designed for adults only. For children and teens, BMI must be interpreted using BMI-for-age percentiles, which account for normal growth patterns. Refer to CDC BMI-for-age growth charts or consult your pediatrician.
Is this calculator suitable during pregnancy?
No. BMI calculations during pregnancy and the postpartum period are not reliable indicators of health status. Weight gain during pregnancy is normal and expected. Speak with your OB-GYN or midwife for individualized guidance.
What about athletes and muscular individuals?
BMI can be misleading for individuals with high muscle mass. Muscle weighs more than fat by volume, so a highly muscular person may have a “overweight” or “obese” BMI while being in excellent health. If this applies to you, consider body composition assessments (like DEXA scans) for a more accurate picture.
What is a “good” BMI to target?
For most adults, a BMI between 18.5 and 24.9 is associated with the lowest health risks. Many health professionals reference BMI 22 as a commonly used midpoint target. However, the “best” BMI for you depends on your individual health profile — discuss with your clinician.
⚠️ Important Disclaimer
This calculator is not medical advice. BMI is a screening tool and does not diagnose health or directly measure body fat. The Reverse BMI Calculator is intended for adults only and provides an estimate of the weight/height/BMI relationship based on the standard BMI formula — not a recommended “goal weight.”
Special populations — including children/teens, pregnant or postpartum individuals, athletes with high muscle mass, and those with certain medical conditions — should not rely on BMI alone. Consult a qualified healthcare professional for personalized assessment and guidance.