BMI Calculator
What is BMI?
Body Mass Index (BMI) is a simple numerical measure that uses your weight and height to estimate body fat for most adults. BMI is calculated using the formula: BMI = weight (kg) ÷ height (m²). Clinicians and public health organizations use BMI to screen for weight categories that may lead to health problems, such as high blood pressure, diabetes, and cardiovascular disease.
How to calculate your BMI
To compute BMI manually: measure your weight in kilograms and your height in metres, square your height, then divide weight by the squared height. For example, if you weigh 70 kg and are 1.75 m tall: 70 ÷ (1.75 × 1.75) = 22.86. That value falls in the “healthy” range.
BMI Categories (adult)
The World Health Organization (WHO) categories commonly adopted are:
- Underweight: BMI < 18.5
- Normal weight: BMI 18.5 – 24.9
- Overweight: BMI 25 – 29.9
- Obesity: BMI > 30
These bands are useful for population screening — but individual health depends on many factors including muscle mass, bone structure, and fat distribution.
Benefits and limitations of BMI
Benefits: BMI is fast, inexpensive, and widely used for population-level risk assessment. It helps guide public health policy and raises awareness around weight-related health risks.
Limitations: BMI does not distinguish muscle from fat. Athletes with high muscle mass may have an elevated BMI but low body fat. Older adults may have normal BMI but high body fat with low muscle mass. For nuanced assessment, use our Body Fat Calculator or Lean Body Mass Calculator.
What to do with your BMI result
If your BMI is outside the healthy range, consider these steps:
- Consult a healthcare professional for personalized assessment.
- Track diet and physical activity — try our Calorie Calculator and TDEE Calculator.
- For performance or aesthetic goals, pair BMI with body composition tools such as body fat percentage and waist circumference.
FAQs
What is a good BMI for my age?
A good BMI depends on your age and overall health, but generally the healthy range of 18.5–24.9 applies to most adults. For seniors, doctors may consider slightly higher BMIs acceptable.
What is the average BMI for a 70 year old?
The average BMI for a 70 year old is often slightly higher than younger adults, with many falling in the 23–28 range. Maintaining a BMI around 23–27 is considered healthy for seniors.
What is the ideal weight according to height and age?
Ideal weight is calculated using BMI and height. While age doesn’t change the BMI formula, older adults may be advised to maintain a slightly higher BMI for health and strength.
Should your BMI be higher as you age?
Yes, as people age, having a slightly higher BMI (in the 23–28 range) may be beneficial, since being slightly underweight can increase health risks in older adults.
How to calculate BMI with age and height?
BMI itself is only based on height and weight, not age. However, age is considered when interpreting BMI results. Use our BMI calculator by entering your height and weight.
Is BMI calculated differently for seniors?
No, BMI is calculated the same way for all adults, but the interpretation may vary. Seniors may be considered healthy at slightly higher BMI ranges.
How much should a 5 foot 5 inch 70 year old woman weigh?
For a 70-year-old woman who is 5’5”, a healthy weight is generally between 115 and 150 pounds, depending on body composition and overall health.
Is a 23 BMI chubby?
No, a BMI of 23 is within the normal, healthy range (18.5–24.9). It is not considered chubby.
How much BMI is chubby?
A BMI between 25 and 29.9 is considered overweight, which some people call “chubby.”
How many pounds is 23 BMI?
The number of pounds at a BMI of 23 depends on your height. For example, at 5’7” a BMI of 23 is about 150 pounds.
Is BMI 23 attractive?
A BMI of 23 is within the healthy range and often considered fit and attractive. However, attractiveness is subjective and varies by culture and preference.
What BMI is considered stocky?
A BMI between 25–29.9 (overweight category) may be considered stocky, especially if muscle mass is high.
What size is BMI 23?
A BMI of 23 is typically a medium build and corresponds to a healthy weight for most heights.
What BMI to qualify for Wegovy?
To qualify for Wegovy, you usually need a BMI of 30 or greater, or 27 or greater with weight-related health issues.
What are the requirements to qualify for Wegovy?
The main requirements are a BMI ?30, or BMI ?27 with conditions like diabetes or high blood pressure. A doctor’s prescription is necessary.
What does your BMI have to be to be on Wegovy?
You must have a BMI of at least 30, or 27 with comorbidities, to qualify for Wegovy.
What disqualifies you from taking Wegovy?
You may be disqualified if you do not meet the BMI requirement, have certain medical conditions, or if your doctor determines it is not safe for you.
Is it hard to get approved for Wegovy?
Approval depends on BMI, health conditions, and insurance coverage. Many patients with BMI ?30 qualify if prescribed by a doctor.
What does your BMI have to be to qualify for Zepbound?
Like Wegovy, Zepbound typically requires a BMI ?30, or ?27 with related health issues.
Why is BMI no longer used?
BMI is still widely used, but it has limitations because it does not measure body fat directly. It may not accurately reflect health for athletes or older adults.
Why don’t we use BMI anymore?
Doctors still use BMI, but many combine it with other tests such as waist circumference, blood tests, and body fat measurements for a clearer picture of health.
What is replacing BMI?
Some experts recommend using body fat percentage, waist-to-hip ratio, or other metrics instead of BMI alone.
What is the controversy with BMI?
The controversy is that BMI does not account for muscle, bone density, age, sex, or ethnicity, which can misclassify some people’s health.
Does BMI still exist?
Yes, BMI is still the most common tool to quickly estimate weight category and health risk.
Is a BMI of 17.6 anorexic?
A BMI of 17.6 is below the healthy range and may be considered underweight. If caused by eating disorders, it may be classified as anorexic.
What is Tom Brady’s BMI?
Tom Brady reportedly has a BMI around 27, which is technically overweight, but due to his muscle mass, he is actually very fit.