BMI Calculator: Calculate Your Body Mass Index

Calculate BMI

Body Mass Index Explained

BMI, or Body Mass Index, is a number that tells us about our body size compared to our height.

It helps us see if we’re underweight, normal weight, overweight, or obese.

Even though it’s helpful for a quick look at our body, it doesn’t know the difference between muscles and fat, so it’s not perfect.

People often use it with other health checks to get a better picture of how healthy they are.

BMI Ranges for Adults

These BMI range categories give a general idea of where someone might fall based on their BMI:

BMI RangeCategory
Below 18.5Underweight
18.5 to 24.9Normal Weight
25.0 to 29.9Overweight
30.0 and aboveObesity
via the NIH

However, it’s crucial to note that BMI has limitations and doesn’t consider factors like muscle mass or distribution of fat.

Individual health should be assessed holistically, and BMI should be used as part of a broader health evaluation.

How to Calculate Your Body Mass Index

Body Mass Index (BMI) is calculated by dividing a person’s weight in kilograms by the square of their height in meters. The formula is:

BMI =  Weight (kg) / Height (m)²

Pros & Cons of BMI

Pros of BMI:

  1. Health Assessment: BMI is often used as a quick and easy tool to assess whether an individual falls into underweight, normal weight, overweight, or obese categories.
  2. Public Health Studies: On a population level, BMI is useful in public health studies to analyze trends in weight and assess the prevalence of obesity-related health issues.
  3. Clinical Screening: BMI is used as a screening tool in clinical settings to identify individuals who may be at risk for health issues associated with weight, such as diabetes and heart disease.
  4. Treatment Planning: For some medical treatments, including surgeries, knowing a patient’s body mass can be crucial in planning and assessing potential risks.

Cons of BMI:

  1. Limited Precision: BMI does not differentiate between muscle and fat, so it may misclassify individuals with high muscle mass as overweight or obese.
  2. Doesn’t Consider Body Composition: BMI doesn’t account for variations in body fat percentage or distribution, which are critical factors in assessing health.
  3. Cultural and Ethnic Variations: BMI standards are based on Western populations and may not be suitable for all ethnic and cultural groups, leading to potential misclassifications.
  4. Age and Gender Differences: BMI standards are not adjusted for age and gender, which can be limiting, especially in assessing children and older adults.
  5. Mental Health Impact: For some individuals, the focus on BMI may contribute to body image issues and unhealthy dieting behaviors.

It’s essential to use body mass calculations alongside other health indicators and assessments for a more comprehensive understanding of an individual’s health.

More Body Composition Calculators


Comments

18 responses to “BMI Calculator: Calculate Your Body Mass Index”

  1. Brian J Boyce Avatar
    Brian J Boyce

    This must be for young kids. If my body weight was out of the over weight classification the frigging wind would blow me over. Better re-check your calculations.

    1. Hey Brian,

      Can you let me know your height and weight so I can double check? Did you make sure to use the Imperial/American and not Metric calculations or vice versa depending on which you are used to?

      1. I’m 5’10 185

        1. Thanks Brian.

          Ok, so the BMI calculation is correct. Technically you have a BMI of 26.5, but that is inherently the problem with BMI is that it doesn’t take into account various things like muscle mass, fat distribution, bone structure, etc.

          BMI is really a first pass measure and is flat out wrong in many cases. I would suggest looking at alternative calculations…we’ve listed some here -> https://bmicruncher.com/alternatives-to-bmi/

  2. Quetelet’s BMI – which he himself stated should never be used as a fat assessor – has been around since about 1830. Nearly relevant as a health eval, as it ignores – given that it was intended as a very general categorical tool by a guy not even in medicine ~ both body type (mesomorph, ectomorph, endomorph), and composition. Better is a waist-to-height calc (waist size = to or smaller than half your height). Best is fat %.,

    1. Yep! You can find our Waist-to-Height Calculator here:

      https://bmicruncher.com/waist-to-height-calculator/

  3. Everett Avatar

    I’m 5’10 and 120 pounds

  4. Laura Carberry Avatar
    Laura Carberry

    Seems to be the only thing my Drs office looks at as health indicator. I need to be 104 lbs to be out of the overweight category. I am 5’2.5″. I have lost 40 lbs recently. My last Drs appointment I was 164 lbs. I know I still need to lose more wt. When I looked at the Drs summary from my appointment it said that my weight was 290 lbs and I was 5 5. WTF

    1. Yeah, unfortunately a lot of our current care is very reactionary based and uses very wide ranges of measurement. Hopefully that will improve in the coming years as we as a society shift to a prevention based approach.

    2. You are full of it. I’m 5’2 and normal weight is 132 or less. You’re being dramatic saying 104.

      1. Sandra l skelton Avatar
        Sandra l skelton

        I’m 5feet 2 inches. No way can I weigh 110 pounds as I would look sick and too small.

  5. Kelsey Avatar

    What could be a reason for not being able to lose any weight no matter what I try. I have been struggling with an unhealthy amount of extra weight that just hit me drastically in a short period of time with no change in my diet or lifestyle or really an idea as to why it just happened out of nowhere. I’m 32 I’ve had 4 kiddos all normal pregnancies. I work in healthcare and we go hiking and are always outside always moving. I don’t really eat but that’s not new I have never really had an appetite or eaten much at all my whole life I am nauseous a lot. I just recently had my gallbladder removed but I’ve been struggling with the weight far before that. I’ve always been fit and not perfect but on the smaller side, healthy. I literally doubled in size in less than two months and can not for the life of me get rid of the weight or figure out why. Doctors look at me like I’m nuts but I’m uncomfortable and honestly disgusted in my own skin. I am in pain most the time and find it impossible to do the things I love to do let alone move. Any advice or ideas on what to do doctors just look at me like some obese person who is lazy and overeats I can’t seem to get anyone to listen or take me seriously. Any suggestions would be greatly appreciated.

    1. Hey Kelsey,

      I’m so sorry to hear you’re going through this!

      Unexplained weight gain with no lifestyle changes can be incredibly frustrating and concerning.

      It’s important to understand that I’m not a medical professional, and I can’t diagnose or offer specific treatment plans.

      However, given the sudden, unexplained weight gain and the additional symptoms you mentioned (nausea, pain, difficulty moving), it’s crucial to see a doctor who can do a thorough evaluation.

      It sounds like that absolutely hasn’t happened yet. What type of doctors have you seen so far? I would certainly try another Primary Care Physician and/or go straight to an Endocrinologist if your health plan allows for it.

      Here are some tips for advocating for yourself during your next doctor’s visit:

      1. Come prepared with a list of your symptoms, including how long they’ve lasted and their severity.
      2. Write down any questions you have for your doctor beforehand.
      3. Consider mentioning any research you’ve done on unexplained weight gain.
      4. Be persistent and assertive about your concerns.

      This sounds like a very difficult situation, and I wish you all the best in finding answers and getting back to feeling like yourself again. Don’t give up on advocating for your health.

      I wish I had more answers for you, but like I said, just keep going. Don’t give up until you figure out the root cause and get a diagnosis.

  6. Beverly Butler Avatar
    Beverly Butler

    You need to fix your calculator. This incorrect information can lead someone to an eating disorder.

    1. The calculation is a standard formula.

      And like we say it can be widely inaccurate depending on your body type and body composition.

      BMI is a good starting point, but never the end all be all.

  7. I’m 25 199lbs 5’10 I’ve lost 31lbs in 5 weeks 🙏 I’m trying to get to at 175lbs see my 6 pack already 🙄

  8. Basim Ahmed Avatar
    Basim Ahmed

    Are you kidding me? I am a man. You gave me the bmi of a woman! This can’t be correct!. And you want me to pay for your plans, I don’t think so 🤔 😏.

    1. There is no difference between BMI classifications for men and women. So your BMI is your BMI regardless of your body composition.

      That’s also why it’s not entirely the best measurement. Check out our Body Fat Calculator for a bit better estimate of your overall health: https://bmicruncher.com/body-fat-calculator/

      Also, not selling anything here. Just providing free health assessment tools!

Leave a Reply

Your email address will not be published. Required fields are marked *