Weight Loss

How to Calculate Your Body Mass Index

BMI can be an indicator of certain health risks. Here’s how to easily calculate your BMI.
How to Calculate Your Body Mass Index
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Updated on January 3, 2023
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Body mass index, or BMI for short, is a measure of body weight based on your height.

For decades, BMI has been a way to measure whether someone is at a healthy weight. In general, people are considered overweight if their BMI is over 25. If their BMI is over 30, they have obesity.


But BMI is not a perfect measurement of overall health, because it doesn't differentiate the weight from fat from the weight from muscle or bone. As a result, a person with a lot of muscle mass and low fat mass may be considered overweight based solely on their BMI.

In addition to looking at your BMI measurement, you can look at other health indicators, including body composition, waist circumference, and genetic or metabolic factors to better understand your overall health.


Since BMI is a measurement that is still widely used, read on to figure out how you can calculate it on your own.

How to Calculate Your BMI Using a BMI Chart

If you're an adult, locate your height in inches (remember, there are 12 inches in each foot) and your weight in pounds on the BMI chart at the bottom of the article.

Where those numbers intersect is your BMI, which will be in the normal (healthy), overweight, or obesity range.

If your weight and height are not in this sample chart, use the mathematical equation in the chart at the bottom of the article to find out where you fall.

Or use a free BMI calculator offered by the Centers for Disease Control and Prevention (CDC) if arithmetic isn't your thing.

What the BMI Numbers Mean

A BMI between 18.5 and 24.9 is considered normal weight.


A high BMI is an indicator for overweight or obesity. Obesity and being overweight can increase your risk of health issues, including cancer, stroke, heart disease, and type 2 diabetes.


But keep in mind that your BMI number isn't the be-all and end-all of your health, because it cannot distinguish excess fat, muscle, and bone mass. Also, it does not describe the distribution of fat in the body.


If you're looking for a child's BMI, use BMI percentile, which estimates a child or young person's weight compared with his or her peers of the same age, height, and sex.

 

The Takeaway

  • BMI, or body mass index, is a measurement of body weight based on height.
  • For decades, BMI has been used to determine if a person is at a healthy weight.
  • The measurement is not perfect, since it does not differentiate between weight as a result of fat and weight related to muscle or bone.
  • It's relatively easy to calculate your BMI if you know your height and weight.

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Sean Hashmi, MD

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Sean Hashmi, MD, is an experienced nephrologist and obesity medicine specialist based in Southern California. As the regional director for clinical nutrition and weight management at a prominent healthcare organization in Southern California, Dr. Hashmi oversees the development and implementation of cutting-edge nutritional programs and weight management strategies. With his innovative approach and unwavering commitment to providing evidence-based solutions, he is a highly sought-after speaker and a leader in his field.

Hashmi founded the nonprofit organization SelfPrinciple.org to provide accessible and accurate health, nutrition, and wellness information to the public. Through this platform, he shares the latest research findings, empowering individuals to make informed decisions about their well-being. Self Principle also supports children's education by providing scholarships, books, and supplies, so that students have the resources necessary to succeed academically and build a brighter future.

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Melinda Carstensen

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Melinda Carstensen is an award-winning reporter, copywriter, and editor who specializes in health and wellness media. She joined Everyday Health in 2017 and is an editorial director overseeing lifestyle and wellness coverage for Everyday Health and Lose It! She previously worked as an editor at Fox News Health, Patch.com, and Disney’s Babble.com, and her writing has appeared in SELF and Weight Watchers Magazine.

Carstensen received her bachelor's degree in journalism from the University of Florida, and was the lifestyle editor and university editor at the Independent Florida Alligator, the largest student-run paper in the United States. She enjoys getting outdoors for a run or a hike, catching up with friends over a glass of red wine, or unplugging by cracking open a novel. She lives in Rochester, New York, with her family.

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Resources
  1. Obesity and Cancer. National Cancer Institute. April 5, 2022.
  2. AMA adopts new policy clarifying role of BMI as a measure in medicine. American Medical Association. June 13, 2024.
  3. Body Mass Index in Adults. American Heart Association. January 16, 2024.
  4. Health Risks of Overweight & Obesity. National Institute of Diabetes and Digestive and Kidney Diseases. May 2023.
  5. Body Mass Index (BMI). Cleveland Clinic. May 9, 2022.