How to test your body composition

  • 1 Minute Read
Ryan Newhouse - health writer, MyNetDiary

Have you wondered how to test your body composition? Knowing your percentage of body fat and muscle mass can help you look beyond just weight to redefine your personal weight loss goals. There are a variety of test methods available. Read on to learn more.

How to test your body composition

Different options to test your body composition

There are a variety of body composition tests available to tell you how much of your body is muscle versus fat mass. If you choose not to rely on how your jeans fit or what the scale says, take it a step further by learning how to test your body composition using the methods below.

Body fat scale

You can get an at-home scale that uses bioelectrical impedance (BIA) to read lean mass, bone mass, and body fat. However, these scales are not very reliable. Drinking a lot of water before you get on the scale can skew the results by as much as ten percent.

Pinch test

Many gyms and trainers offer skinfold calipers (known affectionately as the "pinch test") to assess body fat. While they can provide decent results, they are also prone to "user error." A trained professional can help you get the most accurate results from calipers.

Bioelectrical impedance analysis (BIA)

A quick and easily accessible test for your body composition, BIA works by passing a current through the body. The current resistance is measured and then plugged into a mathematical equation to reveal total body water, fat-free mass, and body fat.


Used by professional athletes, a BOD POD works by measuring how much air, instead of water, that your body displaces in a specially designed tube. Although pricey and time-consuming, it is one of the most accurate ways to measure body composition.

DEXA scan

Typically used in medical settings to measure bone density, this x-ray can also measure body fat. When estimating body fat, a DEXA scan is the gold standard, boasting an error rate as low as 1-2%. However, it can cost thousands of dollars for a full work-up.

Underwater weighing

Called the "dunk test" or hydrostatic weighing, this test requires you to jump in a pool, curl up on a stool underwater and expel your breath. It can be complicated to perform correctly, but its results are quite accurate. The best place to complete this test is your local college or university.

When you know more about what your body composition tells you, you can make more informed decisions about your health and activity.

Reviewed and updated by Brenda Braslow, MS, RDN, LDN, CDCES on December 16, 2021.

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Weight Loss->Body composition
Jan 14, 2022

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