Calculate body fat percentage using the US Navy's proven circumference-based formula. Send height, weight, and body measurements to GET /v1/health/body-fat for instant results. Works with both metric and imperial units. The Navy method provides reliable estimates without expensive equipment — just requires neck and waist measurements (plus hips for women).
curl "https://tinyfn.io/v1/health/body-fat" \
-H "X-API-Key: YOUR_API_KEY"const response = await fetch('https://tinyfn.io/v1/health/body-fat', {
headers: { 'X-API-Key': 'YOUR_API_KEY' }
});
const data = await response.json();
console.log(data);import requests
response = requests.get('https://tinyfn.io/v1/health/body-fat',
headers={'X-API-Key': 'YOUR_API_KEY'})
data = response.json()
print(data)Connect your AI agent (Claude, Cursor, Windsurf, etc.) to TinyFn's health tools:
{
"mcpServers": {
"tinyfn-health": {
"url": "https://tinyfn.io/mcp/health",
"headers": {
"X-API-Key": "YOUR_API_KEY"
}
}
}
}The US Navy method typically estimates within 3-4% of DEXA scan results. It's more accurate than BMI for athletic builds but less precise than hydrostatic weighing or DEXA scans.
Men need height, weight, neck circumference, and waist circumference. Women also need hip circumference. All measurements should be taken at specific anatomical landmarks for accuracy.
Yes, integrate it into fitness tracking workflows in Cursor or other MCP-enabled editors. The deterministic calculations ensure consistent results when monitoring progress over time.
Yes, the API accepts both metric (cm, kg) and imperial (inches, pounds) measurements. Specify your preferred unit system in the request parameters.
Circumference-based formulas account for muscle mass and body composition, while BMI only uses height and weight. This makes the Navy method more accurate for athletes and muscular individuals.
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