Free Health Calculators for Body, Nutrition & Wellbeing
Evidence-based calculators for BMI, calories, heart rate, pregnancy, sleep, and more — built on WHO-aligned formulas and validated screening frameworks. Educational estimates, no sign-up.
Understand Your Numbers Before You Change Them
Most health goals start with a number: a weight range, a daily calorie target, a resting heart rate. These calculators give you those numbers using evidence-based formulas — WHO-aligned BMI ranges, standard BMR and TDEE equations, and validated screening frameworks such as PHQ-9 and GAD-7 — so your plan starts from an honest baseline.
Start with body metrics to understand where you are, use the nutrition tools to set daily targets, and track heart, sleep, and stress measures as you go. Every tool explains its method and interprets the result in plain language.
Most Popular Health Calculators
All Health Calculators
Body Metrics
8 toolsBMI Calculator
Most popularCheck whether your weight falls in a healthy range for your height using WHO-aligned BMI ranges.
Use calculator →BMI Calculator for Women
BMI with interpretation tailored to women's body composition and life stages.
Use calculator →BMI Calculator for Men
BMI with interpretation tailored to men's typical body composition.
Use calculator →Child BMI Calculator
Age-based BMI percentiles for children and teens.
Use calculator →Body Fat Calculator
Estimate body fat percentage using standard measurement formulas for men and women.
Use calculator →Ideal Body Weight Calculator
Estimate a healthy weight range for your height using established medical formulas.
Use calculator →Lean Body Mass Calculator
Estimate the weight of everything but fat — muscle, bone, and water.
Use calculator →Muscle Mass Calculator
Estimate skeletal muscle mass and see how it compares with typical ranges.
Use calculator →Nutrition & Diet
8 toolsCalorie Calculator
Best for goalsFind daily calorie needs based on age, weight, height, and activity level.
Use calculator →Macro Calculator
Split daily calories into protein, carbohydrate, and fat targets.
Use calculator →Keto Macro Calculator
Macro targets tuned for ketogenic low-carb eating.
Use calculator →Protein Target Calculator
Daily protein intake target based on weight, goals, and training.
Use calculator →Water Intake Calculator
Estimate daily hydration needs from body weight, climate, and activity.
Use calculator →Glycemic Index Calculator
Calculate glycemic load to make blood-sugar-friendly food choices.
Use calculator →Weight Loss Calculator
Plan a calorie deficit and project a realistic weight loss timeline.
Use calculator →Intermittent Fasting Calculator
Plan fasting and eating windows for 16:8, 18:6, and other protocols.
Use calculator →Metabolism & Fitness
7 toolsBMR Calculator
Estimate the calories your body needs at complete rest.
Use calculator →TDEE Calculator
Total daily energy expenditure including activity — the basis for any calorie plan.
Use calculator →Steps to Calories Calculator
Convert daily step counts into estimated calories burned.
Use calculator →Heart Rate Zone Calculator
Training zones for fat burn, endurance, and peak effort from your max heart rate.
Use calculator →VO2 Max Calculator
Estimate aerobic fitness capacity and compare against age-group norms.
Use calculator →Six-Pack Timeline Calculator
Estimate how long reaching visible abs could take at your current body fat.
Use calculator →Fitness Quiz
Quick assessment of your current fitness level with suggested next steps.
Use calculator →Heart & Medical
6 toolsBlood Pressure Calculator
Interpret systolic and diastolic readings against standard categories.
Use calculator →Heart Rate Calculator
Check resting heart rate and target ranges by age.
Use calculator →Blood Sugar Calculator
Interpret fasting and post-meal glucose readings, with unit conversion.
Use calculator →Vitamin D Calculator
Estimate vitamin D needs from sun exposure, diet, and location.
Use calculator →Testosterone Calculator
Understand typical testosterone ranges by age and related lifestyle factors.
Use calculator →BAC Calculator
Estimate blood alcohol concentration from drinks, weight, and time.
Use calculator →Pregnancy & Women's Health
7 toolsPregnancy Calculator
Track pregnancy week by week from your last period or conception date.
Use calculator →Due Date Calculator
Estimate your delivery date and key trimester milestones.
Use calculator →Ovulation Calculator
Predict your fertile window and ovulation day from cycle dates.
Use calculator →Period Tracker
Predict upcoming cycles and understand cycle-length patterns.
Use calculator →Fertility Calculator
Estimate your most fertile days when planning for pregnancy.
Use calculator →Pregnancy Weight Gain Calculator
Check recommended weight gain ranges by trimester and pre-pregnancy BMI.
Use calculator →Postpartum Recovery Calculator
A guide to typical recovery milestones after delivery.
Use calculator →Mind & Sleep
3 toolsMental Health Assessment
Educational screening based on validated PHQ-9 and GAD-7 frameworks.
Use calculator →Sleep Calculator
Find ideal bed and wake times based on natural 90-minute sleep cycles.
Use calculator →Stress Calculator
Gauge current stress load and identify the biggest contributors.
Use calculator →Guides and background
Which Calculator Should You Start With?
If you are new to health tracking, start with BMI to understand your weight range, then BMR and TDEE to see what your body burns in a day. With those three numbers you can set a calorie target that matches your goal — losing, maintaining, or gaining — and use the macro tools to turn it into meals.
- BMI → weight range context
- BMR / TDEE → daily calorie burn
- Calorie + Macro calculators → daily targets
- Water Intake and Sleep → daily habits that support the rest
Estimates, Not Diagnoses
Every formula here is population-based: accurate enough to plan with, but not a measurement of you specifically. Athletes read high on BMI, calorie equations carry a margin of error, and screening tools flag patterns rather than conditions. Use the results to ask better questions — and bring those questions to a healthcare professional.
- Recheck monthly rather than daily — trends beat snapshots
- Combine two or three related tools for a fuller picture
- See a clinician for anything a screening tool flags
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Frequently Asked Questions
Are GlobalCalqulate health calculators medically accurate?
Yes. Our calculations use evidence-based formulas and healthcare standards where applicable (for example, WHO-aligned BMI ranges, commonly used BMR/TDEE estimation equations, and validated mental health screening frameworks such as PHQ-9 and GAD-7). Results are informational estimates and should be interpreted with professional guidance when needed.
Can these calculators diagnose medical conditions?
No. These tools are designed for educational awareness and lifestyle planning only. They do not diagnose, treat, cure, or prevent any disease.
Can I use these health calculators in India / USA / UK / Canada / Australia?
Yes. These calculators work globally and are commonly used as a BMI Calculator India, BMI Calculator USA, BMI Calculator UK, Health Calculator Canada, and more. The formulas are universal; recommendations should be personalized with a clinician for medical conditions.
Do I need to create an account or share personal data?
No. You can use these calculators without creating an account. We do not require personally identifying information to access the tools.
Which health calculator should I start with?
If you're unsure, start with the BMI Calculator to understand weight range. Then use BMR or TDEE to estimate calorie burn. For nutrition targets, use Calorie + Macro calculators. For lifestyle improvement, try Water Intake and Sleep calculators.
Explore All GlobalCalqulate Tools
533+ free calculators across health, finance, education, writing, and conversions — for 11 countries. No sign-up required.
Browse Popular Calculators →Free • No registration • Updated 2026