Body Composition (How to Read InBody)
Last updated: 2026-06-25
On an InBody result, look first at skeletal muscle mass, body fat percentage, and the shape of their bars (C / I / D). Muscle above standard with body fat below standard reads as a D shape (athletic) body.
Standard body fat is generally 10-20% for men and 18-28% for women; this tool grades your input against those ranges.
Enter your body composition numbers
Body fat grade / body type
-
| Item | Value |
|---|---|
| Body fat percentage | |
| Standard body fat range | |
| Fat mass | |
| Fat-free mass (FFM) | |
| Skeletal muscle mass (SMM) | |
| SMM / body weight ratio |
This interpretation is for reference based on general standard ranges. Since body composition is affected by body water, watch the trend under consistent conditions rather than a single reading, and confirm health decisions with a medical professional.
How to use
- Enter sex and weight — Enter your sex and body weight (kg), used to convert fat mass and fat-free mass.
- Enter muscle mass and body fat — Enter the skeletal muscle mass (kg) and body fat percentage (%) from your InBody sheet.
- View results — Press Interpret to see your body fat grade, body type (C / I / D shape), and fat mass / fat-free mass in a table.
How to read InBody - key items and body types
The first things to look at in a body composition (InBody) analysis are skeletal muscle mass and body fat percentage. Connecting those two values and your weight as a bar graph reveals your body type. Low muscle with high fat is a C shape, similar bars are an I shape, and high muscle with low fat is a D shape.
| Group | Low | Standard | High |
|---|---|---|---|
| Male | under 10% | 10-20% | over 20% |
| Female | under 18% | 18-28% | over 28% |
| Type | Characteristics | Direction |
|---|---|---|
| C shape | Low muscle, high fat (includes skinny-fat) | Strength training + fat loss |
| I shape | Weight, muscle, and fat in standard balance | Maintain and improve gradually |
| D shape | High muscle, low fat (athletic) | Maintain and build strength |
Fat-free mass (FFM) is your weight minus fat mass, including muscle, bone, and water. Fat mass is weight x body fat percentage (%). To track training results, watch the rise in skeletal muscle mass and the fall in fat mass together rather than scale weight alone. Check your target weight and protein intake with the macro calculator.
Frequently asked questions (FAQ)
What should I look at first on an InBody result?
Look first at skeletal muscle mass, body fat percentage, and the shape of the bar graph connecting them. If muscle mass is above standard and body fat is below standard, the bars form a D shape, read as a fit, well-trained body.
What are the C, I, and D body types?
They describe the shape of the three bars for weight, skeletal muscle mass, and fat mass. Low muscle with high fat is a C shape (low-muscle, high-fat), similar bars are an I shape (balanced), and high muscle with low fat is a D shape (athletic).
How do standard body fat ranges differ by sex?
Generally a standard range is about 10-20% body fat for men and 18-28% for women. Women have a higher standard for physiological reasons. This tool grades your input against these ranges.
Are skeletal muscle mass and muscle mass the same?
No. Skeletal muscle mass (SMM) refers only to the skeletal muscle of the arms, legs, and trunk, while muscle mass is a broader term that includes smooth and cardiac muscle. To track training results, watch the change in skeletal muscle mass.
What should I avoid before a measurement?
Measure on an empty stomach (2+ hours after eating), after using the restroom, and avoid right after intense exercise or a sauna. Measuring at the same time of day improves consistency since results are affected by body water, so watch the trend.
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Last updated: 2026-06-25