What Is Ideal Body Weight?

Ideal body weight (IBW) is the estimated weight range that is considered optimal for your height, gender, and body frame. It is not a single fixed number — it is a range that reflects what most people of your height and build tend to weigh when they are in good health.

The term was first developed in clinical settings to help calculate safe medication dosages and assess general health risk. Over time, it evolved into a widely used reference point in fitness, nutrition, and preventive health.

Why does ideal body weight matter?

• It gives you a realistic, science-backed target weight to aim for
• It helps you understand whether your current weight puts you at risk
• It supports better conversations with doctors and dietitians
• It serves as a starting point for setting fitness and weight loss goals

Important limitations to keep in mind:
Ideal body weight formulas are useful guides, not medical diagnoses. They do not account for muscle mass, bone density, ethnicity, age-related changes in body composition, or individual metabolic differences. A highly muscular athlete, for example, may weigh more than the "ideal" range while being in excellent health. Always use these numbers as a starting reference, not an absolute standard.

What Is an Ideal Weight Calculator?

An ideal weight calculator is an online tool that estimates your ideal body weight based on a few simple inputs — typically your height, gender, and sometimes age. It applies one or more established medical formulas to generate a personalized weight range within seconds.
Purpose of the calculator:

• Give you an instant, formula-based estimate of your ideal weight
• Show you results from multiple formulas so you can see a realistic range
• Help you set informed, healthy weight goals
• Remove guesswork from the "what should I weigh?" question

Who should use it?

• Anyone starting a weight loss or fitness journey
• People wondering if their current weight is within a healthy range
• Individuals preparing for a health assessment or medical appointment
• Athletes monitoring body weight relative to performance goals
• Anyone simply curious about their ideal weight for their height

How Is Ideal Weight Calculated?

Three main formulas are widely used by healthcare professionals to calculate ideal body weight. Each was developed by a different researcher and produces slightly different results, which is why most calculators show a range rather than a single number.
1. The Devine Formula (1974)
Developed by Dr. B.J. Devine, this formula was originally created to calculate drug dosages. It became one of the most widely referenced ideal weight formulas in medicine.

• For men: starts at 50 kg (110 lbs) for a height of 5 feet, then adds 2.3 kg for every inch above 5 feet
• For women: starts at 45.5 kg (100 lbs) for 5 feet, then adds 2.3 kg per inch above

2. The Robinson Formula (1983)
An updated version that produces slightly lower results than Devine, often considered more appropriate for lighter-framed individuals.

• For men: 52 kg base at 5 feet, plus 1.9 kg per inch above
• For women: 49 kg base at 5 feet, plus 1.7 kg per inch above

3. The Miller Formula (1983)
Generally produces the lowest estimates of the three, often used when a more conservative target is preferred.

• For men: 56.2 kg base at 5 feet, plus 1.41 kg per inch above
• For women: 53.1 kg base at 5 feet, plus 1.36 kg per inch above

None of these formulas require you to do any math yourself. Our ideal body weight calculator runs all three automatically and displays your results instantly.

Ideal Weight for Height — Why Height Is the Most Important Factor

When it comes to estimating your ideal weight, height is the single most powerful variable. Every major ideal weight formula is built around height as its foundation, because taller people naturally have larger bone structures, greater muscle volume, and more organ mass — all of which add to body weight in a completely healthy way.
This is why "ideal weight for height" is the most searched and most clinically relevant way to frame the question. Comparing a 5'2" person's weight to a 6'1" person's weight without accounting for height is simply not meaningful.
How height affects ideal weight:

• Every additional inch of height adds roughly 2–2.5 kg (4.5–5.5 lbs) to the ideal weight range
• Taller individuals have a naturally higher ideal weight — this is expected and normal
• Short-statured individuals should not aim to weigh what taller people weigh

Male vs female differences by height:
Men and women of the same height have different ideal weight ranges. Men generally carry more muscle mass and have denser bone structure, which means their ideal weight is typically 5–10% higher than a woman of the same height.
For example:

• At 5'6" (168 cm): the ideal weight range is roughly 130–155 lbs for women and 139–163 lbs for men
• At 5'10" (178 cm): the range is approximately 146–173 lbs for women and 155–181 lbs for men
• At 6'0" (183 cm): men typically fall in the 160–190 lbs range; women near 152–179 lbs

These are reference ranges — individual results from our calculator may vary slightly based on the formula used and your specific inputs.

How This Calculator Works

Our ideal weight calculator is designed to be fast, accurate, and easy to use. Here is what it asks for and what it gives you back.
Inputs:

• Height — the primary variable in all ideal weight formulas. Enter in feet and inches or centimeters.
• Gender — biological sex affects the base weight value in every major formula. Male and female values differ meaningfully.
• Age — used to contextualize results. Note that the core formulas are height-based, but age helps flag considerations for growing teens or older adults.
• Unit preference — choose between imperial (lbs/inches) or metric (kg/cm)

Output:

• Your ideal weight range from each of the three major formulas
• A composite recommended range showing the lowest and highest values across all formulas
• A simple indicator of where your current weight sits relative to your ideal range

The calculator does not store your data and requires no sign-up. Results are generated instantly in your browser.

Healthy Weight vs Ideal Weight — What's the Difference?

These two terms are often used interchangeably, but they measure slightly different things.
Ideal weight is a formula-based estimate derived from your height and gender. It produces a specific number or narrow range based on mathematical models developed in clinical research.
Healthy weight range is typically defined using BMI (Body Mass Index) — a ratio of your weight to the square of your height. A BMI between 18.5 and 24.9 is generally considered the healthy range for most adults.
Why both matter:

• Ideal weight gives you a height-specific, personalized target
• Healthy weight range tells you whether you fall within a statistically low-risk zone for weight-related health issues
• Using both together gives you a more complete picture than either alone

For most people who are not highly muscular athletes, both measures will point to a similar weight zone. If there is a large gap between the two for you, it may be worth discussing with a healthcare provider.
To explore your BMI alongside your ideal weight, try our BMI Calculator.

Real-Life Examples

Understanding ideal weight in the abstract is one thing — seeing it applied to real scenarios makes it far more useful.
Example 1 — Shorter woman, general health goal
Sarah is 5'2" (157 cm), 34 years old, and wants to reach a healthy weight. Her ideal weight range based on combined formulas is approximately 108–127 lbs (49–58 kg). Her current weight of 138 lbs suggests she is moderately above her ideal range, and a moderate calorie deficit with regular activity could help her reach her goal over 4–6 months.
Example 2 — Tall man, fitness goal
James is 6'1" (185 cm), 28 years old, and regularly lifts weights. His formula-based ideal weight range is approximately 166–194 lbs (75–88 kg). At 195 lbs with visible muscle definition, he is just above the upper end of the formula range — but his body fat percentage is low. This is a perfect example of why ideal weight formulas should be used as a guide, not an absolute rule, for muscular individuals.
Example 3 — Average height woman, weight loss journey
Emma is 5'5" (165 cm) and wants to understand what a realistic goal weight looks like. Her ideal weight range is roughly 122–145 lbs (55–66 kg). Rather than chasing an unrealistically low number she saw on social media, the calculator gives her a science-backed zone to aim for.
Example 4 — Older adult, maintaining health
David is 68 years old, 5'9" (175 cm). His ideal weight range is approximately 149–174 lbs. For older adults, research suggests that being slightly above the lower end of the ideal range can offer some protective benefits. His doctor may recommend aiming for the middle of the range rather than the minimum.

Ideal Weight vs BMI — Which Should You Use?

Both tools are valuable, but they measure different things and have different strengths.
BMI (Body Mass Index):

• Uses your weight and height to calculate a single ratio
• Easy to calculate and widely used by health systems worldwide
• Good for population-level screening
• Does not distinguish between fat and muscle
• Can misclassify muscular individuals as overweight

Ideal Weight Calculator:

• Uses height, gender, and age to estimate a target weight range
• Based on clinical formulas developed specifically for weight assessment
• More nuanced than BMI alone
• Still does not account for body fat percentage or muscle composition

The best approach: use both tools together. If your current weight is above both your ideal weight range and the healthy BMI zone, that's a clearer signal to take action. If one metric says you're fine but the other doesn't, it's worth digging deeper with a body fat assessment.
Pair this calculator with our Body Fat Calculator for the most complete picture of your body composition.

Factors That Affect Your Ideal Weight

The formulas give you a starting point, but several real-world factors influence what a truly optimal weight looks like for your body specifically.
Muscle mass
Muscle is significantly denser than fat. A person with a high level of muscle mass may weigh more than the formula suggests while having a very healthy body composition. For this reason, active individuals and athletes often fall above ideal weight ranges without any health concern.
Body frame size
Some people have naturally larger or smaller bone structures. A person with a large frame will naturally weigh more than someone of the same height with a small frame. Many older versions of ideal weight charts accounted for wrist or elbow breadth as a proxy for frame size.
Age
As people age, body composition naturally shifts — muscle mass tends to decrease and fat tends to increase, even without changes in overall weight. For older adults, what constitutes a healthy weight may differ from what a standard formula suggests.
Gender and hormones
Hormonal differences between men and women affect fat distribution, muscle mass retention, and metabolic rate — all of which influence body weight. Women naturally carry a higher percentage of essential body fat than men.
Ethnicity
Research shows that health risks associated with excess weight can vary by ethnicity. Some health organizations use adjusted BMI thresholds for certain populations. Ideal weight formulas do not currently account for ethnicity.
Lifestyle and activity level
A highly active person — whether through sport, manual labor, or structured exercise — will have different body composition needs than a sedentary person of the same height and gender.
Understanding your full nutritional picture alongside your ideal weight is easier with our Calorie Calculator and Macro Calculator.

Common Mistakes People Make With Ideal Weight

1. Treating the number as a hard rule
Ideal weight ranges are estimates, not precise targets. Obsessing over reaching a specific number on the scale can be counterproductive and misleading if you are also gaining muscle.
2. Ignoring body composition
The scale doesn't tell you whether your weight is coming from fat, muscle, or water. Two people can weigh exactly the same and have entirely different health profiles. Always consider body composition alongside body weight.
3. Comparing yourself to others
Your ideal weight for your height is personal. Comparing your target weight to a friend, celebrity, or social media figure — especially one with a different height, frame, or fitness level — is not useful and often harmful.
4. Setting unrealistic timelines
Sustainable weight change happens at roughly 0.5–1 kg (1–2 lbs) per week. Expecting to move from one end of your ideal range to the other in a few weeks is unrealistic and risks unhealthy habits.
5. Using only one metric
Relying solely on ideal weight without looking at body fat, waist circumference, energy levels, and overall fitness gives an incomplete picture of your health.

Practical Tips to Reach Your Ideal Weight

Diet and nutrition:

• Focus on whole foods — vegetables, lean proteins, whole grains, and healthy fats
• Build meals around protein, which supports muscle retention during weight loss
• Reduce ultra-processed foods and sugary drinks, which add calories without nutritional value
• Track your intake for at least two weeks to understand your actual eating patterns
• Aim for a moderate calorie deficit of 300–500 calories per day if your goal is to lose weight

Exercise and movement:

• Combine cardiovascular exercise (walking, cycling, swimming) with resistance training for best results
• Resistance training helps preserve muscle mass while losing fat — important for maintaining a healthy body composition
• Aim for at least 150 minutes of moderate-intensity activity per week as recommended by health authorities
• Consistency over intensity — regular moderate exercise beats occasional extreme workouts

Lifestyle and mindset:

• Prioritize sleep — poor sleep disrupts hunger hormones and makes healthy weight management much harder
• Manage stress — chronic stress elevates cortisol, which promotes fat storage, particularly around the abdomen
• Set process goals (habits) rather than only outcome goals (the number on the scale)
• Track progress weekly, not daily — daily weight fluctuations are normal and don't reflect true fat loss or gain

If you want to understand how much to eat to support your goals, our Calorie Calculator will give you a precise daily target based on your activity level and weight goal.

Related Calculators You May Find Useful

Getting a complete picture of your health goes beyond ideal weight alone. Here are tools that work well alongside this calculator:

• BMI Calculator — Calculate your Body Mass Index and see which weight category you fall into
• Body Fat Calculator — Estimate your body fat percentage for a deeper look at body composition
• Calorie Calculator — Find out exactly how many calories your body needs each day
• Macro Calculator — Get a personalized protein, carbs, and fat breakdown to support your goals

Planning your health is a lot like planning your finances — small consistent actions compound over time. If you're working toward a bigger life goal alongside your fitness journey, our Savings Goal Calculator and Future Value Calculator can help you see how consistent effort pays off in both areas.

This calculator is intended for informational and educational purposes only. It does not constitute medical advice. For personalized health guidance, please consult a qualified healthcare professional.