Your ideal body weight is an estimated range based on your height, age, and sex. It is not a single magic number. Use this calculator to get a quick estimate, then read below to understand what the result means and where it falls short.
This ideal weight calculator uses several well-known formulas (Devine, Hamwi, Robinson, and Miller) plus BMI-based ranges to give you a practical starting point. Results are estimates. They do not replace guidance from a health professional.
How Much Should I Weigh? What This Ideal Body Weight Calculator Estimates
"How much should I weigh?" is one of the most common health questions online. The honest answer: it depends on more than a single number can capture.
This ideal body weight calculator estimates a range of weight that is generally associated with lower health risks for a person of your height, age, and sex. It pulls from multiple IBW formulas and a healthy BMI range so you can compare approaches side by side.
What does ideal body weight mean? IBW is a clinical estimate originally developed to help with medication dosing. It represents the weight at which a person of a given height is expected to function well metabolically. Over time, the concept expanded into general wellness planning.
Keep in mind: the calculator gives a general guideline. Many factors, including muscle mass, body fat distribution, bone density, and ethnicity, affect what a healthy weight actually looks like for you.
How to Calculate Ideal Body Weight Using This Weight Calculator
Using this weight calculator takes about 10 seconds.
- Enter your height. Choose feet and inches or centimeters (metric).
- Select your sex. The formulas for males and females differ.
- Enter your age. Age is used for the BMI-based range and context notes.
- Click calculate.
The calculator returns results from four IBW formulas plus a BMI-based healthy weight range. You will see numbers in both kg and pounds.
No measurement beyond height is required, but the results section explains when additional data (waist measurement, body fat percentage) would give a fuller picture.
IBW Formulas: Devine, Hamwi, Robinson, and Miller
Four formulas are commonly used by doctors and pharmacists to calculate ideal body weight. Each was developed at a different time and with different reference populations, so they produce slightly different numbers.
Devine formula (1974) The most widely used, especially for medication dosing. For males: 50 kg + 2.3 kg per inch over 5 feet. For females: 45.5 kg + 2.3 kg per inch over 5 feet.
Hamwi formula (1964) For males: 48 kg + 2.7 kg per inch over 5 feet. For females: 45.5 kg + 2.2 kg per inch over 5 feet. Tends to produce slightly higher estimates for taller men.
Robinson formula (1983) For males: 52 kg + 1.9 kg per inch over 5 feet. For females: 49 kg + 1.7 kg per inch over 5 feet. Generally gives lower estimates than Hamwi.
Miller formula (1983) For males: 56.2 kg + 1.41 kg per inch over 5 feet. For females: 53.1 kg + 1.36 kg per inch over 5 feet. Produces the highest baseline but the smallest increments per inch.
Which ideal body weight formula is the best? None is perfect. The Devine formula remains the standard for clinical dosage calculations, but for general wellness the range across all four gives a more useful picture than any single number.
IBW Calculator Results in kg and Pounds
This IBW calculator displays every result in both kg and pounds so you can compare without converting manually. The range across all four formulas often spans 5 to 15 pounds. That spread is normal and reflects the uncertainty built into any formula based only on height and sex.
If your current weight falls within the range, you are likely in a reasonable zone. If it falls outside, consider the additional factors discussed below before drawing conclusions.
Body Mass Index (BMI) and Healthy Weight Range (18.5 to 24.9)
BMI, or body mass index, is a simple ratio: weight in kg divided by height in meters squared. A healthy BMI is between 18.5 and 24.9.
| BMI Range | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 to 24.9 | Normal weight range |
| 25.0 to 29.9 | Considered overweight |
| 30.0 and above | Obesity |
The calculator converts a healthy BMI range into an actual range of weight in pounds and kg for your height. This gives you a broader window than the single-point IBW formulas.
For example, a person 5 feet 6 inches tall has a healthy weight range of roughly 118 to 154 pounds based on BMI. That span is wider than most IBW formula outputs, and intentionally so. It accounts for natural variation in body frame and composition.
Healthy BMI vs. Ideal Weight: How the Measurements Differ
BMI and IBW answer related but different questions.
- IBW estimates a single target weight for your height and sex. It was designed for clinical use, particularly medication dosing for certain drugs.
- BMI classifies where your current weight sits on a population-level risk scale. It defines a range, not a point.
Neither measurement accounts for body fat percentage, muscle mass, or fat distribution. A person with a lot of muscle may have a high BMI yet a healthy body composition. That is why both numbers are best used as starting points, not final answers.
Adjusted Body Weight: When to Use It Instead of IBW
Adjusted body weight (AdjBW) is used when a person's actual weight significantly exceeds their ideal body weight. It matters most in clinical settings for medication dosing and nutritional planning.
The standard formula:
AdjBW = IBW + 0.4 × (Actual Weight − IBW)
This accounts for the fact that excess weight is not purely fat. Some of it is metabolically active lean tissue. Doctors and pharmacists use adjusted body weight when dosing certain drugs to avoid under-dosing in patients with obesity.
For general wellness planning, adjusted body weight is less relevant. If your goal is simply to determine a person's healthy target range, the IBW formulas and BMI range are more practical.
Body Fat Percentage, Muscle Mass, and Body Composition
Body fat percentage measures how much of your total weight comes from fat versus lean body mass (muscle, bone, water, organs). It gives a more complete picture than weight alone.
General body fat percentage guidelines:
| Category | Men | Women |
|---|---|---|
| Essential fat | 2–5% | 10–13% |
| Athletes | 6–13% | 14–20% |
| Fitness | 14–17% | 21–24% |
| Average | 18–24% | 25–31% |
| Above average | 25%+ | 32%+ |
Body composition is the full breakdown: fat, skeletal muscle, bone, and water. Two people at the same height and weight can look and feel completely different depending on their ratio of muscle to fat.
Why Body Fat and Skeletal Muscle Change What a Healthy Weight Looks Like
A person with a lot of muscle will weigh more than the IBW formulas predict, yet may be in excellent health. Conversely, someone at a "normal" weight but with high body fat and low muscle mass (sometimes called "skinny fat") can face elevated health risks.
This is why body fat percentage and muscle mass matter. They explain the gap between what a formula says you should weigh and how healthy you actually are.
Common ways to estimate body composition include skinfold calipers, bioelectrical impedance scales, DEXA scans, and waist measurement. None is perfect, but any of them adds information that height-and-weight formulas cannot provide.
Ideal Weight by Height and Age: Weight Chart for Men and Women
The weight chart below shows approximate ideal weight ranges based on height for adult males and females. Ranges combine the four IBW formulas and a healthy BMI window.
Men
| Height | IBW Range (lbs) | Healthy BMI Range (lbs) |
|---|---|---|
| 5'2" | 123–137 | 115–143 |
| 5'4" | 130–146 | 122–153 |
| 5'6" | 137–155 | 130–163 |
| 5'8" | 144–164 | 139–173 |
| 5'10" | 151–173 | 145–184 |
| 6'0" | 158–183 | 154–195 |
| 6'2" | 165–192 | 164–206 |
Women
| Height | IBW Range (lbs) | Healthy BMI Range (lbs) |
|---|---|---|
| 5'0" | 100–115 | 97–128 |
| 5'2" | 105–122 | 104–137 |
| 5'4" | 110–130 | 112–147 |
| 5'6" | 117–139 | 118–154 |
| 5'8" | 123–148 | 126–164 |
| 5'10" | 130–157 | 132–174 |
| 6'0" | 137–165 | 140–184 |
These are general guidelines. Use the calculator above for your exact height.
How Gender, Body Frame, and Aging Affect Your Healthy Weight Range
Gender. Males typically carry more muscle mass and have higher IBW estimates at the same height. The formulas reflect this with different baseline values for males and females.
Body frame. A person with a larger skeletal frame will naturally weigh more. Some older guidelines use wrist circumference or elbow breadth to estimate frame size. The IBW formulas do not adjust for frame, so consider this if you are notably small- or large-boned.
Aging. A person's age affects body composition. After about age 30, people tend to lose muscle and gain fat gradually, even if total weight stays the same. Metabolism slows. The CDC notes that healthy weight ranges may shift slightly with age, though BMI categories remain the same for adults. Maintaining muscle through exercise becomes more important as you age.
Factors such as age, frame, and activity level are why a range of weight is more useful than a single number.
Overweight, Obesity, and Health Conditions Linked to Body Weight
Being significantly above a healthy weight range increases the risk for developing several serious health conditions. Being underweight carries its own set of risks.
A BMI of 25 or above is considered overweight. A BMI of 30 or above indicates obesity. These thresholds are population-level markers, not individual diagnoses, but they correlate with increased health risks.
Cardiovascular Disease, Diabetes, and Other Risks
Carrying excess weight, especially belly fat around the waist, is associated with:
- Cardiovascular disease (heart attack, stroke, high blood pressure)
- Type 2 diabetes
- Certain cancers
- Sleep apnea
- Joint problems and osteoarthritis
- Fatty liver disease
Waist measurement adds useful context. The CDC considers a waist circumference above 40 inches for men or 35 inches for women (measured at the belly button level) to signal higher risk, independent of BMI.
Fat distribution matters. Two people with the same BMI can have very different risk profiles depending on where their body stores fat. Visceral fat (deep belly fat) is more metabolically dangerous than subcutaneous fat on the hips at its widest.
Being underweight (BMI below 18.5) is linked to nutrient deficiencies, weakened immune function, bone loss, and fertility issues.
Body Mass Index Limitations: What BMI and This Calculator Cannot Tell You
BMI is a screening tool, not a diagnostic one. It has well-documented limitations.
- It does not distinguish between fat and muscle. A muscular athlete can register as overweight or obese based on BMI alone.
- It does not account for fat distribution. Where you carry fat affects health risks more than how much you carry.
- It uses the same thresholds for all ethnicities, though research shows risk levels can vary across populations.
- It does not consider a person's age beyond the adult/child distinction.
The IBW formulas share many of these gaps. They were developed using limited reference populations and rely only on height and sex.
Always consult a health professional if you need a personalized assessment. This calculator is an estimate and a planning aid. It is not a diagnosis.
Pregnancy, Children, and Athletes
Pregnancy. Standard BMI and IBW formulas are not designed for pregnant individuals. Weight gain during pregnancy is expected and healthy. Your doctor can provide trimester-specific guidance.
Children and teens. BMI for children uses age- and sex-specific percentile charts, not the adult thresholds of 18.5 and 24.9. This calculator is intended for adults. The CDC provides separate growth charts for children.
Athletes. People who train intensely often carry significant muscle mass. Their weight may exceed IBW estimates while their body fat percentage and overall health are excellent. Body composition measurements are far more useful than BMI or IBW for athletes.
How to Reach and Maintain a Healthy Weight
If your results suggest your current weight is outside a healthy range, small, sustainable changes tend to work better than drastic ones.
Focus on direction, not perfection. A modest change of 5 to 10 percent of body weight can improve your health significantly if you are overweight.
Exercise, Dieting, and When to Talk to a Doctor
Exercise. The CDC recommends at least 150 minutes of moderate aerobic activity per week, plus two sessions of muscle-strengthening activity. Building muscle increases your metabolic rate and improves body composition, even if the scale does not move much.
Nutrition. Sustainable eating patterns work better than extreme diets. Focus on whole foods, adequate protein, and portions that match your activity level. Crash dieting can cause muscle loss, which makes long-term weight management harder.
When to talk to a doctor. Always consult a health professional if:
- You want to lose or gain weight significantly
- You have existing health conditions affected by weight
- Your BMI is below 18.5 or above 30
- You are considering medication or surgery for weight management
A doctor can assess factors this calculator cannot: bloodwork, hormonal health, family history, and individual risk factors. Use your results here as a conversation starter, not a conclusion.