Conicity index calculator
The conicity index divides your waist in metres by 0.109 times the square root of weight over height, so the higher the score, the more your shape leans toward a double cone with mass around the abdomen. Enter waist and height in cm, weight in kg. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Waist
- 85
- Weight
- 70
- Height
- 170
- Conicity index
- 1.2152562644
- Waist cm
- 85
- Weight (kg)
- 70
- Height (cm)
- 170
The Conicity Index is a classical anthropometric measure of how much a person's body shape resembles a double cone rather than a cylinder of the same mass and height. It is computed from three everyday measurements: waist circumference, body weight, and standing height. Unlike body mass index, which only relates weight to height, conicity explicitly folds in waist size so that two people with the same BMI can receive different scores when one carries more mass around the abdomen. Researchers and educators use the index as a transparent screen for central adiposity and cardiometabolic risk discussions. This calculator applies the Valdez formula exactly, rejects missing or non-numeric inputs, and returns a dimensionless result with the cleaned inputs so products, classrooms, and APIs always agree on the same number.
How the Conicity Index is defined and computed
The Valdez Conicity Index compares measured waist circumference to the waist a perfect cylinder of the same body mass and height would have, using a fixed geometric constant of zero point one zero nine meters. In SI units the formula is C equals waist in meters divided by zero point one zero nine times the square root of weight in kilograms over height in meters. This capability accepts the measurements people actually collect: waist and height in centimeters, weight in kilograms.
The index is dimensionless. Typical adult values often fall roughly between one point zero and about one point five, with higher scores indicating a more conical, abdomen-dominant silhouette relative to total mass. Missing fields, non-numeric strings, NaN, Infinity, zero, and negative values fail early with invalid input rather than returning Infinity or a silent absolute value.
That contract matters for automated pipelines: a bad tape measure reading must not masquerade as a believable conicity score. Educational products should still frame the number as a screening-style estimate, not a medical diagnosis; clinical decisions need qualified professionals and context this tool does not collect.
Where Conicity Index calculators show up in real work
Fitness coaches and digital health apps often teach central-adiposity concepts after BMI and before densitometry or DEXA, so a single transparent oracle that returns the exact Valdez score speeds onboarding copy and demo setup. Research assistants preparing synthetic screening datasets need deterministic conicity labels from waist, weight, and height without network calls or model drift. Public-health workshops and corporate wellness portals often walk through sample adults with tape-measure examples, and clear rejection of zero height or missing weight prevents broken demos.
If you later need body mass index, waist-to-height ratio, waist-hip ratio, basal metabolic rate, or body-fat equations, treat those as separate search intents and landings rather than overloading this conicity-index-calculator page. Always frame results as educational estimates, not medical diagnosis; clinical decisions require qualified professionals and context this tool does not collect.
What you can do with it
Coaching and wellness intake
Compute a transparent Valdez Conicity Index from tape-measure waist, scale weight, and height before deeper body-composition work.
Classroom and public-health demos
Generate deterministic conicity scores for lesson sets so teachers and auto-graders share one ground truth including invalid-input rejection.
FAQ
What is the Conicity Index?
It is a dimensionless anthropometric index from Valdez that compares measured waist circumference to the waist expected for a cylinder of the same mass and height. Higher values indicate more central (abdominal) fat distribution.
Which formula do you use?
The constant 0.109 is the classical Valdez geometric factor.
What happens if a field is missing or not a number?
All three fields (waist, weight, height) must be finite numbers strictly greater than zero. Failed validation is not charged.
How is this different from BMI or waist-to-height ratio?
BMI uses only weight and height. Waist-to-height ratio uses only waist and height. Conicity Index uses waist, weight, and height together, so it specifically gauges how conical the silhouette is relative to total mass.
What does it cost?
The browser tool is free and runs locally.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/health/conicity-index \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"waist":85,"weight":70,"height":170}'const res = await fetch("https://api.kit.forhosting.com/health/conicity-index", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"waist": 85,
"weight": 70,
"height": 170
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/health/conicity-index",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"waist": 85,
"weight": 70,
"height": 170
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/health/conicity-index", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"waist":85,"weight":70,"height":170}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"waist":85,"weight":70,"height":170}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/health/conicity-index", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"waist": 85,
"weight": 70,
"height": 170
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "health.conicity_index",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
How the Conicity Index is defined and computed
Because the math is pure arithmetic, identical inputs always produce identical JSON with no network calls, no random jitter, and no date dependence.
What you send and what you get back
Send three required fields. When height is zero or negative the error message states that height is zero or negative so the Conicity Index is undefined or non-physical, matching the product rule that division by zero and non-physical geometry never appear as results. Convert inches to centimeters before calling if your forms collect imperial lengths, and keep mass in kilograms so the Valdez constant remains consistent with published SI literature. Waist is circumference in centimeters and must be a finite number strictly greater than zero; aliases waist_cm, waist_circumference, and circumference are accepted. Weight is body mass in kilograms and must also be finite and strictly greater than zero; aliases weight_kg, mass, and body_weight are accepted. Height is standing height in centimeters, finite and strictly greater than zero; aliases height_cm and cm are accepted. On success the response returns conicity_index as the cleaned dimensionless score, the cleaned waist_cm, weight_kg, and height_cm echoes, SI echoes waist_m and height_m, the constant zero point one zero nine, unit dimensionless, the formula string, method valdez_conicity_index, and a short educational note that higher values indicate more central fat distribution. Classic smoke checks include an eighty-five centimeter waist, seventy kilogram body mass, and one hundred seventy centimeter height for a mid-range adult score, and an intentionally blank weight for the invalid_input path. Pricing for successful API calls is the published base of $0.002 per item; validation failures do not consume prepaid balance.
Where Conicity Index calculators show up in real work
Secondary-school and college health classes assign conicity drills alongside waist-to-height ratio and waist-hip ratio so students see why waist-normalized indices can flag risk when BMI looks normal; matching hand arithmetic to API output matters more than asymptotic cost. Because this capability is a pure parse engine, API pricing is the published base of $0.002 per successful item and failed validation does not consume balance.
Integration use cases
App and API fixtures
Bulk-produce golden Conicity Index JSON for onboarding flows and regression tests without network calls or non-deterministic models.