BMI Calculator

The Body Mass Index (BMI) Calculator should be used to calculate your BMI Value.  Some people think this isn't the best way of determining if you're in shape or not but it's one of the most used worldwide metrics to determine where you're at.  You can use the 'US Units' tab for those in the US and for the rest of earth - you can use the 'Metric Units' drop down on the 'Systems' drop-down.  

BMI Introduction

BMI is a person's weight in killograms divided by the square of height in meters.  It's not a complicated measure and if you're a healthy with a high amount of muscle mass, it's typically not the best measure but it's one you can use to determine for the doctor.  It's an easy screening method to put you into a category from Underweight all the way up to Obesity.  Below you'll see a few charts that can tell you what a 'healthy' BMI looks like. 

This does NOT measure body fat directly but it is strongly correlated with various metabolic and disease outcome so it's worthwhile to always understand what your BMI is.  There is more intel below the calculator once you determine your BMI but let's get started!

BMI Calculator

Source: This BMI Chart is a visualization of the output of the number you got above.  Please keep track of where you're at but you should be between 18.5-24.9 BMI to be in the 'normal' range.  

Here's another visual graph of BMI categorized by the World Health Organization.  This chart was taken from this source and is another way of visualizing where you are on the BMI chart. 

BMI Chart for Adults

The chart to the left is used for Adults but there are other charges the CDC uses for age specific growth that is different for boys and girls.  Please use the chart above for Adults!

If you're looking for a BMI Calculator for Children or teens - please go to the CDC site here

The other aspects to consider with BMI are the risks with being overweight, underweight and just overall limitations of BMI. 

Risks of being Underweight

According to, there are six major risks for being underweight.  These risks include: 

  • malnutrition, vitamin deficiencies, or anemia
  • osteoporosis from too little vitamin D and calcium
  • decreased immune function
  • increased risk for complications from surgery
  • fertility issues caused by irregular menstrual cycles
  • growth and development issues, especially in children and teenagers

If one of these reasons isn't enough to eat more - I don't know what is.  Please use the Calorie Calculator or Macro Calculator to figure out how much more you need to eat to get into the healthy / normal range. 

Risks of being Overweight

According to, the biggest health problems and risks associated with being overweight are: 

  • type 2 diabetes
  • high blood pressure
  • heart disease and strokes
  • certain types of cancer
  • sleep apnea
  • osteoarthritis
  • fatty liver disease
  • kidney disease
  • pregnancy problems, such as high blood sugar during pregnancy, high blood pressure, and increased risk for cesarean delivery (C-section)

Some other numbers they recommend considering besides being in the healthy range for BMI are taking a look at the following: 

  • Waist Size
  • Blood Pressure
  • LDL (Bad Cholesterol) 
  • HDL (Good Cholesterol) 
  • Triglycerides
  • Blood Sugar

Limitations of BMI

The BMI is a widely used measurement of health but it does have quite a few limitations.  It would be crazy to think that one number is going to tell you how healthy (or unhealthy) you might be.  It's important to take into consideration all the reasons above when thinking about your health.  

BMI is a measure of excess body weight, that excess body weight could be muscle so some of the largest and healthiest people might be fine but are 'Overweight' or 'Obese' because of the amount of muscle their body is holding.  In athletes and bodybuilders this can be a real issue and according to the Center for Disease Control: 

  • Older adults tend to have more body fat that young adults with the same BMI 
  • Women typically have more bodyfat than men even with the same BMI 
  • Muscular people and highly trained athletes need to consider other factors due to the large amount of muscle mass their body is holding


While BMI is a wonderful metric that is widely used across the globe, it does have it's limitations.  It's important to know where you are on the scale but if you're a highly trained athlete and it tells you you're obese - don't freak out.  Please make sure you're using other factors to determine your health.  

We all want to be healthy and at Tabata Times want to provide as much information as possible but we are not health experts.  Please consult your health provider to determine what you need to do.  Each body and person is unique so use this as one metric and consider all others when determining your health. 

If you're looking for what you amount you should eat to maintain, gain or lose weight - use some of our other tools like: 

  • Calorie Calculator 
  • Macro Calculator 
  • Tabata Timer - this can be used for some quick bursts of high intensity interval training 

Until next time - stay BMI normal!