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Waist Circumference Calculator

Calculating waist circumference is a simple way to help assess obesity, focusing on body fat in the abdominal region, which is close to major organs that are often damaged by excessive weight. In January 2025, an international commission suggested that BMI alone is insufficient in defining obesity. More details below, including calculator usage.

Inches/Centimeters

Related Calculators: Waist to Height, Waist to Hip

Calculator Usage

Waist Circumference: Enter your waist circumference, or that of the person for whom you are calculating.

Gender: Specify gender, as the assessment, as determined by various medical organizations, is based on gender.

Measurement in: Indicate if the waist circumference is in inches or centimeters.

How to Measure Waist Circumference

Circumference is the distance around your waist.

Using a flexible tape measure, measure your waistline, as follows:

  1. Place your thumbs on your Iliac Crest, which is the very top, rounded area of your hip bone.

  2. Now, swing your middle finger toward the center of your stomach, so they meet just above your belly button. You are at your waistline! Place the end of the tape measure here.

  3. Wrap tape measure completely around your waist until it meets the starting end, keeping it parallel to the floor.

  4. Breath out slowly, tightening measurer. It should be snug, but not digging into your skin.

  5. Take your reading at end of exhalation.

  6. Repeat above steps again to make sure your reading is accurate.

YouTube video: how to measure waistline.

Problems with BMI and Obesity

Since the 1970s, Body Mass Index (BMI) has been the screening test employed by doctors and healthcare professionals to determine if someone is underweight, overweight, or obese. BMI is calculated using a person's weight (in kilograms) divided by height squared (in meters).

Many medical professionals and researchers have believed for some time that BMI is often inaccurate, particularly because it can not differentiate between lean muscle mass and body fat; BMI can not distinguish between subcutaneous fat, just under the skin, or visceral fat, which is deep within the abdomen.

In January 2025, a global Commission comprised of 56 experts released a report in The Lancet Diabetes & Endocrinology, indicating, among other important points, that BMI, stand-alone, is insufficient to measure obesity and should be used in conjunction with other anthropometric measures of adiposity (which means obesity, or inclination to become obese) or direct measurement of fat via a DXA scan (more below).

How is Obesity Being Re-Defined

Given that about 1 billion people globally (as of the 2020s), or about 1/8th of the world's population, is obese, the The Lancet Diabetes & Endocrinology Commission has redefined obesity into two distinct categories:

  • Preclinical Obesity is where someone has excess fat but no current organ damage, nor are there disruptions to everyday life, such as occurs with joint problems. Preclinical obesity puts one at risk for future diseases. While treatment is not currently called for, it can open the discussion regarding lifestyle changes, or for medical intervention (such as a Semaglutide like Wegovy® or Ozempic®) to avert advancing to Clinical Obesity.

  • Clinical Obesity, where excess weight has resulted in organ damage causing a variety of medical conditions, including high blood pressure, Type 2 diabetes, heart disease and stroke, osteoarthritis, and some cancers. Medical intervention is required. With Clinical Obesity, obesity is now considered a disease in and of itself.

What is an Anthropometric Measure?

Anthropometric pertains to studying the human body based on measurements and proportions.

For instance, waist is the body measurement used on this Waist Circumference calculator to determine if it is within a healthy range, or puts one at risk for health issues.

What are Anthropometric Calculations for Obesity?

Body Mass Index (BMI) is an Anthropometric measure used for decades. More recently, the following are also being used, with research showing they can be more effective for obesity screening, since they focus on body fat location, in particular central obesity (i.e. fat located in abdominal region).

  • Waist Circumference (WC) - Uses your waist circumference; Use this calculator to determine if your WC is within the normal range or a health risk.

  • Waist to Hip Ratio (WHR) - Uses your waist circumference and hip circumference. WHR Calculator

  • Waist to Height Ratio (WHtR) - Uses your waist circumference compared to height. WHtR Calculator

Why Does Fat Location Matter?

As it turns out, and has been known for many years, the location of fat in the body is important when evaluating if someone's excess weight is a health risk.

Fat located in the buttocks and thighs, known as gluteofemoral fat, for instance, typically does not put one at risk for major health diseases. That is, assuming it is not accompanied by central obesity.

Mid-section body fat, on the other hand, is generally visceral fat, which means it is deep within the abdomen, where it is more likely to get into or obstruct proper functioning of vital organs including the liver and heart, potentially resulting in a multitude of health issues, from diabetes to cardiovascular disease.

What are Cutoff Levels for Waist Circumference

Assessing waist circumference is different for women and men:

Waist Circumference Women

If a woman's waist circumference is greater than 35 inches (88 centimeters), it poses a health risk.

Waist Circumference Men

If a man's waist circumference is greater than 40 inches (102 centimeters), it poses a health risk.

What is a DXA Scan to Measure Fat

Unlike Anthropometric Measurements, another tool for measuring obesity is the Dual X-Ray Absorptiometry, also knowns as a DXA (or DEXA) Scan.

During a DXA scan, a wand passes over the body, providing information on body composition: lean fat and visceral fat, as well as bone density for which the test was originally created in the late 1980s for diagnosing osteoporosis and osteopenia.

What are Advantages of Waist Circumference Screening?

Waist Circumference focuses on one location: the abdomen, where excess weight or obesity is known to cause many diseases, particularly cardiovascular, stroke, diabetes, as well as everyday health issues such as joint problems in the knees and back.

This is in contrast to BMI, which compares weight to height, but is essentially unaware of where in the body the fat is located or its composition.

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All information provided on this calculator is for informational purposes only. It is not intended as a substitute for advice provided by a medical doctor or qualified healthcare provider. You should not use this information for self-diagnosis or for treating a health problem. If you have any questions whatsoever about your medical health or believe you have a medical problem or disease, you should contact your medical doctor or healthcare provider.