| Metric | Value | Copy |
|---|---|---|
| {{ r.label }} | {{ r.value }} |
| Category | Range % | Copy |
|---|---|---|
| {{ r.label }} | {{ r.range }} |
| Category | Range | Copy |
|---|---|---|
| {{ r.label }} | {{ r.range }} |
Body composition is the balance of fat and lean tissue in the body, a practical way to track health and training progress over time. Use this body fat percentage calculator using tape measurements to turn everyday readings into clear numbers you can compare.
You provide your sex, height, weight, and two tape measurements at the neck and waist, and women also add the hips. The result includes body fat percent, body mass index, and a split into lean mass and fat mass so you can see both proportion and weight.
Results are grouped into familiar ranges so a small shift is easy to spot and a bigger change stands out, and a quick glance tells you whether you sit near a boundary or well inside a band. Numbers depend on careful tape placement and posture, so repeat measurements the same way.
For example, a man at 170 centimetres and 70 kilograms with a 38 centimetre neck and 80 centimetre waist comes out near 13.7 percent body fat with a BMI around 24.2, with lean mass about 60.4 kilograms and fat mass about 9.6 kilograms.
Use consistent technique, measure at rest, and remember that athletic builds or pregnancy can shift interpretation. This tool provides informational estimates and does not substitute professional advice.
Body fat percentage expresses how much of total body mass is adipose tissue. Body mass index (BMI) compares weight to height to indicate broad weight categories. The calculator also estimates fat mass and lean mass to show composition in both percentage and kilograms.
The body fat estimate uses the U.S. Navy circumference method based on height and specific circumferences. Males use neck and waist; females use neck, waist, and hips. Computation is performed in inches for the logarithms, with automatic conversion from centimetres if entered.
Results are interpreted with category bands for body fat and BMI. Values near a threshold should be read cautiously because small tape or scale differences can flip the label without reflecting a meaningful change.
Optional adjustments apply after computation: body fat can be scaled and offset, and BMI can receive a constant offset. Body fat is limited to 0–75 % and BMI to 0–150.
| Symbol | Meaning | Unit/Datatype | Source |
|---|---|---|---|
| Standing height (for formula) | in | Input | |
| Waist circumference | in | Input | |
| Neck circumference | in | Input | |
| Hip circumference (female) | in | Input | |
| Body weight | kg | Input | |
| Body fat percentage | % | Derived | |
| Body mass index | kg/m² | Derived | |
| Fat mass | kg | Derived | |
| Lean mass | kg | Derived | |
| Body fat scale multiplier | unitless | Input (Advanced) | |
| Body fat additive offset | percentage points | Input (Advanced) | |
| BMI additive offset | BMI points | Input (Advanced) |
| Sex | Category | Lower % | Upper % | Interpretation |
|---|---|---|---|---|
| Male | Essential | 2 | 5 | Minimal required fat. |
| Male | Athlete | 6 | 13 | Typically trained physique. |
| Male | Fitness | 14 | 17 | Active lifestyle. |
| Male | Average | 18 | 24 | Common range. |
| Male | Obese | 25 | 100 | Above recommended. |
| Female | Essential | 10 | 13 | Minimal required fat. |
| Female | Athlete | 14 | 20 | Typically trained physique. |
| Female | Fitness | 21 | 24 | Active lifestyle. |
| Female | Average | 25 | 31 | Common range. |
| Female | Obese | 32 | 100 | Above recommended. |
| Category | Lower | Upper | Implication |
|---|---|---|---|
| Underweight | 0 | 18.49 | Below recommended. |
| Normal | 18.5 | 24.9 | Common target band. |
| Overweight | 25 | 29.9 | Elevated risk indicator. |
| Obese | 30 | 100 | High risk indicator. |
| Field | Type | Min | Step/Pattern | Error Text |
|---|---|---|---|---|
| Sex | Select (male/female) | — | — | — |
| Height | Number | 0 | 0.1 | Height must be greater than 0. |
| Weight | Number | 0 | 0.1 | — |
| Neck | Number | 0 | 0.1 | Neck must be greater than 0. |
| Waist | Number | 0 | 0.1 | Waist must be greater than 0. |
| Hip (female) | Number | 0 | 0.1 | Hip must be greater than 0 for female formula. |
| Constraint (male) | Relation | — | — | For males, waist must be larger than neck. |
| Constraint (female) | Relation | — | — | For females, waist + hip must be larger than neck. |
| Neck/waist/hip adjustments | Number | — | 0.1 | Positive adds; negative subtracts (cm). |
| Body fat scale | Number | — | 0.01 | Multiplier; 0 is ignored and treated as 1. |
| Body fat add | Number | — | 0.1 | Adds percentage points after scaling. |
| BMI add | Number | — | 0.1 | Adds to computed BMI. |
Calculations run on your device and no server calls are made for your inputs. Clipboard and file downloads occur locally. Health metrics here are estimates and not medical advice.
Body composition estimation converts a few measurements into body fat, BMI, and a lean‑versus‑fat split.
Example: Enter 170 cm, 70 kg, neck 38 cm, waist 80 cm (male). You will see about 13.7 % body fat and BMI 24.2 with lean 60.4 kg and fat 9.6 kg.
Pro tip: lock in your tape spots with a photo or note so future readings match the first session.
The body fat estimate follows the U.S. Navy circumference method using height plus neck and waist for males and height plus neck, waist, and hips for females.
It provides practical estimates from tape measurements. Tight tape placement, posture, and breath can shift results. Treat trends as more informative than single points.
No server storage is used. Values are computed on your device. Copy and download actions create local data you control.
Length accepts centimetres or inches and weight accepts kilograms or pounds. Internally, formulas use inches for the logarithms and kilograms/metres for BMI.
Height, neck, and waist must be greater than zero. For males, waist must be larger than neck. For females, waist plus hips must be larger than neck.
If your value sits near a category edge, small measurement noise can flip the label. Track the number itself and re‑measure to confirm direction.
Yes. Use the body fat multiplier and additive offset to align with another method, then keep those settings fixed for consistent comparisons.
Calculations do. Visuals and icons require their assets to be available. If charts do not appear, the numeric results still apply.
Usage terms depend on the host page. Review the site’s terms for permissions and any restrictions before redistributing derived values.