Body Fat Calculator

Calculators REST API MCP

Estimate body fat percentage, fat mass, lean mass, BMI, and a body-composition category. Uses the U.S. Navy circumference method (waist, neck, hip) or a BMI-based estimate (Deurenberg formula). Metric (kg/cm) or imperial (lbs/in) inputs.

This page documents the HTTP endpoint POST /api/tools/body-fat-calculator/execute. See the MCP reference →

Use in the browser View as Markdown

Call it over REST

POST https://api.findutils.com/api/tools/body-fat-calculator/execute · no API keys · 60 requests/min per IP

Execute — verified arguments

curl -X POST https://api.findutils.com/api/tools/body-fat-calculator/execute \
  -H "Content-Type: application/json" \
  -d '{
    "gender": "male",
    "weight": 70,
    "height": 175,
    "waist": 85,
    "neck": 38
  }'

Parameter schema for this endpoint

curl https://api.findutils.com/api/tools/body-fat-calculator

Interactive docs · OpenAPI 3.1 spec · All REST tools

Input schema

Argument	Type	Required	Description
gender	string (male \| female)	yes	Biological sex used by the formulas.
weight	number	yes	Body weight in kg (metric) or lbs (imperial).
height	number	yes	Height in cm (metric) or inches (imperial).
unit_system	string (metric \| imperial)	no	Unit system for all measurements. Default: "metric".
method	string (navy \| bmi)	no	"navy" = U.S. Navy circumference method (needs waist, neck, and hip for female). "bmi" = BMI-based estimate. Default: "navy".
waist	number	no	Waist circumference at the navel (cm or in). Required for the navy method.
neck	number	no	Neck circumference below the larynx (cm or in). Required for the navy method.
hip	number	no	Hip circumference at the widest point (cm or in). Required for the navy method when gender is female.
age	integer	no	Age in years. Only used by the bmi method. Default 30. Default: 30.

Example arguments (verified)

{
  "gender": "male",
  "weight": 70,
  "height": 175,
  "waist": 85,
  "neck": 38
}

Also an MCP tool

Claude, Cursor, and any MCP client can call this tool as findutils:body_fat_calculator after one connect command.

Connect once

claude mcp add findutils --transport http https://mcp.findutils.com/

Open the MCP reference for Body Fat Calculator →

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