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    Free Health Calculators 2026 – BMI, Calories, Body Fat & More

    Achieve your health goals with CalcPlanet's evidence-based health calculators. Calculate BMI, daily calorie needs, body fat percentage, ideal weight, macros, hydration, and much more — all based on validated medical formulas.

    ✓ 104 All Online Calculators✓ No login required✓ Mobile Ready

    Most searched in this category

    BMI CalculatorCalorie CalculatorBMR CalculatorBody Fat CalculatorIdeal Weight

    Most Popular

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    BMI🔥

    Calculate your Body Mass Index and instantly see your weight category with health guidance.

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    Calories / BMR

    Calculate your daily calorie needs (BMR and TDEE) based on age, gender, weight, height, and activity level.

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    BMR

    Calculate your Basal Metabolic Rate (BMR) and daily energy expenditure (TDEE).

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    Weight Loss

    Calculate your calorie deficit and timeline for your weight loss goal.

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    Water Intake

    Calculate your daily water needs based on weight and activity level.

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    Keto

    Calculate your daily macros for a ketogenic diet.

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    Calorie Deficit

    Calculate the daily calorie deficit needed for weight loss.

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    Pregnancy Week

    Calculate how many weeks pregnant you are and your due date.

    All Health & Fitness Calculators (104)

    ⚖️BMI🔥Calories / BMR🏋️Body Fat⚖️Ideal Weight🤰Due Date🔥BMR🥗Macros🤱Pregnancy🥩Protein🏃Pace🏋️1 Rep Max❤️Heart Rate Zone🌺Ovulation🍺BAC⚖️Weight Loss💧Water Intake🥑Keto🪖Army Body Fat✅Healthy Weight👙Bra Size👗Body Type📏Height Compare🫘GFR / Kidney🔥TEF🔥Calorie Deficit🤰Pregnancy Week☀️SPF Protection🦶Steps → Calories🥗Macro Split🌾Fiber Intake🫁VO2 Max🍺Alcohol Calories😴Sleep Debt🚶Walking Calories🥗Macro Ratio🚭Quit Smoking⏱️IF Calculator❤️HR Zones🏃Fitness Age💧Hydration🥗Macro from Calories📏Waist-Hip Ratio🚴Cycling Calories👶Child BMI🪑Posture Score❤️Life Expectancy🔥Calorie Burn🥗Macro Goals😴Sleep Quality🏃Running Pace👣Step Count⚖️BMI Imperial🍺Alcohol Calories🎯Calorie Goal🌸Period Tracker💪FFMI🧬Biological Age🏃Marathon Predictor⚖️Surplus / Deficit🥩Protein Per Meal🔥Calories by Activity👶Due Date Countdown🔬Detection Times🍺Alcohol Detection🍺Beer Detection🍷Wine Detection🥃Spirits Detection🌿THC Detection⚡Cocaine Detection💊MDMA Detection🔮Ketamine Detection💊Benzo Detection🍄LSD Detection🍄Shroom Detection⚡Speed Detection⚠️Meth Detection⚗️3-MMC Detection⚡How Long Does Cocaine Stay in Urine?⚡How Long Does Cocaine Stay in Blood?⚡Cocaine Comedown: Duration & Recovery Timeline🌿How Long Does THC Stay in Urine?🌿How Long Does THC Stay in Blood?🌿How Long Does THC Stay in Saliva?🌿THC Detection Time for Frequent & Daily Cannabis Users🌿How Long Do THC Edibles Stay in Your System?💊How Long Does MDMA Stay in Urine?💊How Long Does MDMA Stay in Blood?💊MDMA Comedown: Duration & Serotonin Recovery Timeline🔮How Long Does Ketamine Stay in Urine?🔮Ketamine Detection Time in Saliva Tests🔮How Long Does Ketamine Stay in Your System?🍺How Long Does Alcohol Stay in Urine?🍺How Long Does Alcohol Stay in Blood?🍺Alcohol Recovery Timeline: From Hangover to Full Recovery🍺How Long Does Beer Stay in Your System?⚡How Long Does Amphetamine Stay in Urine?⚡Amphetamine Recovery Timeline: Comedown to Full Recovery⚠️How Long Does Methamphetamine Stay in Urine?⚠️Methamphetamine Recovery Timeline: From Crash to Healing💊How Long Do Benzodiazepines Stay in Urine?💊Benzodiazepine Withdrawal Timeline & Safety Information🍄How Long Does LSD Stay in Your System?🍄How Long Does Psilocybin Stay in Your System?⚗️How Long Does 3-MMC / Mephedrone Stay in Your System?

    BMI & Body Composition

    Body Mass Index (BMI) is a widely used screening tool to assess healthy weight ranges. Our BMI calculator supports both metric (kg/cm) and imperial (lbs/inches) units, with immediate interpretation of results and healthy range guidance.

    Calorie & Nutrition Calculators

    Understanding your calorie needs is the foundation of any diet plan. Our TDEE (Total Daily Energy Expenditure) and BMR (Basal Metabolic Rate) calculators factor in your age, gender, weight, height, and activity level to give you a personalized daily calorie target.

    Fitness & Performance

    Calculate your target heart rate for fat-burning and cardio training zones, find your 1-rep max for strength training, estimate calories burned during exercise, and track your pace for running and cycling.

    Pregnancy & Women's Health

    Our due date calculator, pregnancy week tracker, ovulation calculator, and pregnancy weight gain guide support expectant mothers through every stage of pregnancy with clinically-based estimates.

    Health & Fitness Calculators Guides

    All Guides →
    How BMI Is Calculated – Formula, Ranges & Limitations
    Learn exactly how BMI is calculated, what your BMI score means for health, and the important limitations of BMI as a health metric.
    How Many Calories Should You Eat Per Day? Complete Guide
    Find out your exact daily calorie needs based on age, weight, height, and activity level. Includes TDEE formula and weight loss/gain targets.
    How to Calculate Body Fat Percentage – Methods & Formulas
    Learn 4 ways to calculate body fat percentage including formulas, accuracy comparisons, and healthy body fat ranges by age and sex.
    What Is TDEE? Total Daily Energy Expenditure Explained
    TDEE (Total Daily Energy Expenditure) is how many calories your body burns per day. Learn how to calculate TDEE, use it for weight loss, and set your calorie goals.
    How to Calculate a Calorie Deficit for Weight Loss
    Learn exactly how to calculate your calorie deficit for weight loss. Find your TDEE, set the right deficit size, and use a calorie calculator to hit your goals.
    How BMR Is Calculated – Basal Metabolic Rate Formulas
    Learn how Basal Metabolic Rate (BMR) is calculated using the Mifflin-St Jeor and Harris-Benedict formulas. Includes examples and explains how to use BMR for weight management.

    Popular Health & Fitness Calculators Calculations

    Frequently searched calculations — answered instantly with formulas and step-by-step explanations.

    Calories for a 70 kg womanHow many calories per day to lose weightIdeal weight for 5'8" maleBody fat percentage for menBMR for 30-year-old maleMacro calculator for fat loss

    Health & Fitness Calculators Formula Reference

    All Formulas →
    BMI Formula – Body Mass Index Calculation ExplainedBMR Formula – Basal Metabolic Rate CalculationCalorie Burn Formula – How to Calculate Calories BurnedIdeal Weight Formula – How to Calculate Your Ideal Body WeightCalorie Formula – BMR and TDEE CalculationWaist-to-Hip Ratio Formula – Health Risk AssessmentTarget Heart Rate FormulaTDEE Formula – Total Daily Energy Expenditure

    Frequently Asked Questions

    How is BMI calculated?▼
    BMI = Weight (kg) ÷ Height² (m²). For imperial: BMI = (Weight in lbs ÷ Height in inches²) × 703. A BMI of 18.5–24.9 is considered healthy. Our BMI calculator supports both metric and imperial units.
    How many calories should I eat per day?▼
    Daily calorie needs depend on your BMR (Basal Metabolic Rate) and activity level. Use the Mifflin-St Jeor equation to find your BMR, then multiply by an activity factor (1.2–1.9). Our TDEE calculator does this automatically.
    What is body fat percentage and how do I calculate it?▼
    Body fat percentage measures the proportion of fat tissue to total body weight. Use the U.S. Army method (neck, waist, hip circumference) or skinfold measurements. Healthy ranges: 10–20% for men, 18–28% for women.
    What is the difference between BMR and TDEE?▼
    BMR (Basal Metabolic Rate) is the calories your body burns at complete rest. TDEE (Total Daily Energy Expenditure) includes BMR plus calories burned through activity. TDEE = BMR × Activity Factor.
    How do I calculate my ideal weight?▼
    Several formulas exist: Devine (men: 50 + 2.3 kg per inch over 5ft; women: 45.5 + 2.3 per inch), Robinson, and Hamwi. Our ideal weight calculator shows results from all major methods simultaneously.
    ✓ Documented formulas — all tools use standard industry formulas✓ Updated regularly — content reviewed 2026✓ Used by thousands daily✓ Free — no sign-up required

    See also

    🔢 Mathematics💰 Finance