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VitaCalculator

Health calculators built for clarity.

Science-backed health metrics, based on trusted methodologies and explained in plain language. Pick a calculator below.

Based on WHO CDC NIH Mifflin-St Jeor Devine
BMI
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BMI Calculator

Body Mass Index, classified with the WHO standard.

WHO BMI Classification
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BMR

BMR Calculator

Basal Metabolic Rate via the Mifflin-St Jeor equation.

Mifflin-St Jeor Equation
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TDEE

TDEE Calculator

Total Daily Energy Expenditure and maintenance calories.

Mifflin-St Jeor Equation Activity Multipliers
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IBW

Ideal Weight Calculator

Reference body weight from the Devine and Robinson formulas.

Devine Formula Robinson Formula
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WHR

Waist-to-Hip Ratio Calculator

Body fat distribution, classified by the WHO method.

WHO Waist-Hip Ratio Methodology
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How it works

A number you can actually trust.

VitaCalculator covers the metrics people search most — BMI, BMR, TDEE, ideal weight, and waist-to-hip ratio — each based on a recognized standard and explained in plain language.

01

Enter your measurements

Choose metric or imperial units and type in your numbers. Nothing is saved or sent anywhere.

02

Calculated in your browser

The math runs locally using published formulas. Your measurements never leave your device.

03

Understand the result

Every number comes with plain-language context, the exact formula, and the sources behind it.

Why VitaCalculator

A calmer way to understand your numbers.

Most calculator sites give you a number and nothing else. We focus on clarity, transparency, and trust.

Science-backed & transparent

Every result comes from a published formula or recognized standard — and we show you the exact equation and sources behind it.

Privacy-first

Calculations run entirely in your browser. Your measurements are never sent to a server or stored anywhere.

Clear & fast

Mobile-first, lightweight, and built to explain. Each number comes with plain-language context, not just a figure.

The complete guide

The modern destination for trusted health calculators

VitaCalculator is a modern health calculator platform that helps you calculate and understand the health measurements that matter most. Every health calculator on the site is built on a trusted, internationally recognized formula — so the number you get is one you can actually rely on. From a quick BMI check to a full daily-calorie estimate, VitaCalculator brings accurate health metrics together in one clean, fast, privacy-first experience.

What is VitaCalculator?

Rather than burying you in hundreds of cluttered tools, VitaCalculator focuses on a small, carefully curated set. Each one gives a clear result, the methodology behind it, and plain-language insight into what the number means for your health, fitness, and wellness. Every tool supports both metric and imperial units, so you can explore every calculator in one place or jump straight to the metric you need.

Health methodologies we use

Every VitaCalculator tool is grounded in published, peer-reviewed formulas and recognized standards. We document the exact equation and link to the primary source on every page, so you can always verify where a result comes from.

  • WHO BMI Classification The World Health Organization's international standard for categorizing body mass index in adults.
  • Mifflin-St Jeor Equation The modern gold standard for estimating basal metabolic rate, validated as more accurate than older equations.
  • Devine Formula A widely used reference for ideal body weight, originally developed for clinical medication dosing.
  • Robinson Formula A complementary ideal-weight reference derived from a different population dataset.
  • WHO Waist-to-Hip Ratio Guidelines The WHO measurement method and sex-specific risk thresholds for body-fat distribution.

You can read more about our approach on the methodology page, which explains our sources, references, and educational purpose in full.

What you can calculate

The BMI calculator — a true body mass index calculator — estimates body fat from your height and weight using the official WHO classification, in both metric and imperial units, and shows your weight category alongside your personal healthy weight range. The BMR calculator (basal metabolic rate calculator) estimates the calories your body burns at complete rest with the Mifflin-St Jeor equation, giving you a baseline before activity is layered on.

The TDEE calculator turns that BMR into maintenance calories using an activity multiplier — a daily calorie calculator showing what it takes to maintain, lose, or gain weight. The ideal weight calculator estimates a healthy target weight from your height and sex using the Devine, Robinson, and Miller formulas, shown side by side as a clear range. And the waist-to-hip ratio calculator measures how body fat is distributed using the WHO method, returning your ratio and a sex-specific risk classification.

Methodology

Transparent by default.

We believe a health number is only useful if you can trust where it came from. So we show our work — every time.

Read our methodology
  • We cite the formulas behind every calculation.
  • We cite the published sources we rely on.
  • We do not provide medical advice or diagnosis.
  • All calculations run locally in your browser.

FAQ

Frequently asked questions

What is a health calculator?

A health calculator is an online tool that turns simple measurements — like your height, weight, age, and sex — into a meaningful health metric using a published formula. VitaCalculator offers free health calculators for BMI, BMR, TDEE, ideal weight, and waist-to-hip ratio, each based on an internationally recognized methodology.

How accurate are online health calculators?

Online health calculators are as accurate as the formulas behind them and the measurements you provide. VitaCalculator uses peer-reviewed, internationally accepted equations such as the WHO BMI classification and the Mifflin-St Jeor equation, so results are a reliable estimate. They are population-level screening figures, not individual diagnoses.

Is VitaCalculator free to use?

Yes. Every calculator on VitaCalculator is completely free, with no account, sign-up, or payment required. You can use any health calculator as many times as you like.

Which formulas does VitaCalculator use?

We use internationally recognized standards: the WHO classification for BMI and waist-to-hip ratio, the Mifflin-St Jeor equation for BMR and TDEE, and the Devine, Robinson, and Miller formulas for ideal weight. Each page documents its exact formula and links to the original source.

Can health calculators diagnose medical conditions?

No. Health calculators provide educational estimates based on published formulas and cannot diagnose any medical condition. VitaCalculator results are for informational purposes only and should not be considered medical advice. Always consult a qualified healthcare professional for personal guidance.

What is the difference between BMI and body fat percentage?

BMI estimates whether your weight is in a healthy range relative to your height, but it does not measure body fat directly or distinguish muscle from fat. Body fat percentage measures the proportion of your body made up of fat tissue. The two are related but not interchangeable — a muscular person can have a high BMI with low body fat.

How do I calculate my daily calorie needs?

First calculate your BMR (the calories you burn at rest) with the BMR calculator, then multiply it by an activity factor using the TDEE calculator. The resulting Total Daily Energy Expenditure is your estimated maintenance calories — the number you would eat to keep your weight stable.

What is TDEE?

TDEE stands for Total Daily Energy Expenditure — the total number of calories you burn in a typical day, including rest, movement, and exercise. It is your BMR multiplied by an activity multiplier and is often called your maintenance calories.

How is ideal body weight calculated?

Ideal body weight is estimated from your height and sex using reference formulas such as Devine, Robinson, and Miller. Each adds a per-inch increment above five feet to a base weight. VitaCalculator shows all three side by side as a range rather than a single 'correct' weight.

What is a healthy waist-to-hip ratio?

Using WHO thresholds, a waist-to-hip ratio below 0.90 for men and below 0.80 for women is classified as low risk. Higher ratios indicate more fat carried around the abdomen, which is associated with greater cardiometabolic risk.

Does VitaCalculator support metric and imperial units?

Yes. The BMI, BMR, TDEE, and ideal weight calculators all support both metric (kg, cm) and imperial (lb, ft/in) units, converting internally before calculating, so you can work in whichever system you prefer.