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Professional-grade physique calculators trusted by athletes and fitness enthusiasts worldwide. 100% free, always.

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Nutrition & Lifestyle

Fuel Your Body the Right Way

Calculate your exact macros, TDEE, and ideal weight — then read expert articles that show you what to do with those numbers.

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Health & Science

Understand Your Body From the Inside

From BMI to body fat — our tools translate complex health science into simple, actionable numbers you can use today

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Live Well, Feel Your Best

Sleep, stress, recovery, and daily habits — the lifestyle choices that determine how your body looks and feels every single day.

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OurPhysique — BMI, Body Fat, TDEE, Macros & Ideal Weight Tools
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5 Professional Physique Tools

Every tool you need to track, measure, and build your best physique

BMI Calculator

Body Mass Index gives you a quick snapshot of whether your weight is in a healthy range for your height. Use it as a starting point, not the full picture.

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What is Body Mass Index (BMI)?

BMI is a simple measurement that uses your height and weight to estimate whether your body weight falls within a healthy range. It was developed in the 1830s by Belgian mathematician Adolphe Quetelet and remains the most widely used screening tool in healthcare today.

The Formula

Metric: BMI = weight (kg) ÷ height (m)²  |  Imperial: BMI = (weight in lbs × 703) ÷ height (inches)²

BMI Categories (WHO Standard)

BMI Range Category Health Implication
Below 18.5 Underweight May indicate nutritional deficiency
18.5 – 24.9 Normal Weight Associated with lowest health risk
25.0 – 29.9 Overweight Increased risk of some conditions
30.0 and above Obese Higher risk of chronic disease

Important Limitations

BMI cannot distinguish between muscle and fat. A muscular athlete may have a high BMI while being extremely healthy. Always use BMI alongside other metrics like body fat percentage and waist circumference for a complete picture of your health.

Body Fat Calculator

Uses the US Navy Method — one of the most accurate non-invasive body fat estimation formulas. Enter measurements in cm or inches.

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What is Body Fat Percentage?

Body fat percentage is the proportion of your total body weight that consists of fat tissue. Unlike BMI, it directly measures body composition — giving a far more accurate picture of your health and fitness level.

The US Navy Method

This calculator uses the US Navy circumference method, developed for the United States military. Studies show it has an accuracy margin of approximately ±3–4% compared to DEXA scans.

Male: %BF = 495 ÷ (1.0324 − 0.19077 × log₁₀(waist − neck) + 0.15456 × log₁₀(height)) − 450

Healthy Body Fat Ranges

Category Men Women
Essential Fat 2–5% 10–13%
Athletic 6–13% 14–20%
Fitness 14–17% 21–24%
Average 18–24% 25–31%
Obese 25%+ 32%+

TDEE Calculator

Total Daily Energy Expenditure — the exact number of calories your body burns every day. The foundation of any successful diet or muscle-building program.

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Your Daily Calorie Burn

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What is TDEE?

TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns in a single day — your basal metabolic rate (BMR) plus all calories burned through physical activity.

The Formula Used

This calculator uses the Mifflin-St Jeor equation, considered the most accurate BMR formula for the general population by the Academy of Nutrition and Dietetics.

Male BMR = (10 × weight kg) + (6.25 × height cm) − (5 × age) + 5
Female BMR = (10 × weight kg) + (6.25 × height cm) − (5 × age) − 161

How to Use Your TDEE

Goal Daily Calories
Fat Loss TDEE minus 500 kcal
Maintain Weight TDEE
Muscle Gain TDEE plus 300 kcal
Aggressive Bulk TDEE plus 500 kcal

Macros Calculator

Get the exact grams of protein, carbohydrates, and fats you need daily based on your goal and body weight.

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Daily Calories

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Protein
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Carbs
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Fats

What Are Macronutrients?

Macronutrients are the three main nutrients your body needs in large quantities: protein, carbohydrates, and fats. Each plays a distinct role in body composition, energy levels, and overall health.

Protein (4 kcal per gram)

Protein is the building block of muscle tissue. A general guideline is 1.6–2.2g per kg of bodyweight for those building or maintaining muscle.

Carbohydrates (4 kcal per gram)

Carbohydrates are your body's primary energy source, especially during high-intensity exercise. They fuel your workouts and support recovery.

Fats (9 kcal per gram)

Dietary fats are essential for hormone production, joint health, and absorption of fat-soluble vitamins (A, D, E, K). Never drop fat below 20% of total calories.

Ideal Body Weight Calculator

Discover your ideal weight range using three proven formulas (Hamwi, Devine, Robinson). Enter height in cm or ft+in.

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What is Ideal Body Weight?

Ideal Body Weight (IBW) is an estimated weight range considered optimal for a person of a given height and frame size. It is widely used in medicine to determine appropriate medication dosing, nutritional needs, and health risk assessment.

Three Formulas Combined

Formula Developed By Year
Hamwi Dr. G.J. Hamwi 1964
Devine Dr. B.J. Devine 1974
Robinson Robinson et al. 1983

Important Note

IBW is a guideline, not a target. Factors like muscle mass and bone density mean two people of the same height can have very different healthy weights. Use this alongside body fat percentage for a complete picture.

Expert Knowledge

The Physique Blog

Science-backed articles on health, fitness, nutrition, and lifestyle

Nutrition

Complete Guide to Macros for Beginners: Protein, Carbs and Fats Explained

The first serious diet I ever ran, I lost fifteen pounds and somehow came out the other side...

OurPhysique Team Jun 1, 2026
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Health & Science

How to Calculate Body Fat Percentage at Home: 5 Methods That Actually Work

A while back I spent ninety dollars on a smart scale that promised to track my body fat....

OurPhysique Team May 30, 2026
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Nutrition

What Is TDEE and How to Use It for Weight Loss

My friend Marcus kept his TDEE saved as a screenshot on his phone. 2,412 calories, from a calculator...

OurPhysique Team May 11, 2026
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Health & Science

What Is BMI and Why Does It Matter? The Complete Guide

I’ll be honest with you about something before we start. I used to think BMI was basically nonsense,...

OurPhysique Team May 7, 2026
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View All Articles →

Expert Knowledge

Frequently Asked Questions

Everything you need to know about our tools and physique tracking

 
Are all the tools on OurPhysique completely free?

Yes — every calculator on OurPhysique is 100% free to use with no sign-up, no subscription, and no hidden fees. We believe everyone deserves access to quality fitness tools.

Our BMI calculator uses the standard WHO formula, and our Body Fat calculator uses the US Navy Method — one of the most accurate non-invasive methods available. Results are estimates and should be used as a guide alongside professional advice.

TDEE (Total Daily Energy Expenditure) is the total number of calories your body burns each day. It is the foundation of any diet plan — whether you want to lose fat, maintain weight, or build muscle, knowing your TDEE is the essential first step.

Use our Macros Calculator — select “Muscle Building” as your goal and set your activity level. The calculator will give you exact daily targets for protein, carbohydrates, and fats based on your body weight and activity level.

No. The tools and articles on OurPhysique are for informational and educational purposes only. Always consult a qualified healthcare professional or certified nutritionist before making significant changes to your diet or exercise routine.

Absolutely. OurPhysique is fully responsive and works perfectly on all devices — smartphones, tablets, and desktops.

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