SmartBMIcalc

Free BMI Calculator for Humans & Pets

Instantly check your BMI or your pet's weight health. Get expert-approved ranges, personalized tips, and print-friendly reports—powered by SmartBMIcalc.

Calculate My BMI Calculate Pet BMI

What is BMI?

Body Mass Index (BMI) is a numerical value derived from an individual's weight and height. It provides a simple way to categorize a person as underweight, normal weight, overweight, or obese.

How BMI is Calculated

The BMI formula is:

BMI = weight(kg) / height²(m)

In imperial units:

BMI = 703 × weight(lb) / height²(in)

BMI Categories

  • Below 18.5: Underweight
  • 18.5 – 24.9: Normal weight
  • 25.0 – 29.9: Overweight
  • 30.0 – 34.9: Obesity (Class 1)
  • 35.0 – 39.9: Obesity (Class 2)
  • 40 and above: Severe Obesity

Note: BMI is a screening tool and not a diagnostic tool. It has limitations as it doesn't directly measure body fat or account for factors like muscle mass, bone density, or distribution of fat.

Human BMI Calculator

Calculate your Body Mass Index and get personalized recommendations

Pet BMI Calculator

Calculate your pet's Body Condition Score and get health recommendations

Get Smarter About Your Health—and Your Pet’s

Doctor-Approved Accuracy

Uses WHO-standard BMI formulas trusted by healthcare professionals. No guesswork—just reliable results.

Personalized Health Plan

Not just a number—get actionable diet, exercise, and lifestyle tips tailored to your BMI.

Printable Health Reports

Download/share PDFs with your doctor or trainer—perfect for tracking progress over time.

No-Fluff Health Guides

Learn how BMI really works with science-backed articles on nutrition, exercise, and weight management.

Pet Health Tracker

Vet-designed tool to check if your dog or cat is overweight—with breed-specific healthy ranges.

BMI Questions Answered (For Humans & Pets)

BMI (Body Mass Index) evaluates if your weight matches your height. Formula:

  • Metric: Weight (kg) ÷ [Height (m)]²
  • Imperial: (Weight (lbs) ÷ [Height (in)]²) × 703

Example: 68kg ÷ (1.75m × 1.75m) = 22.2 BMI (normal).

Limitations by group:

  • 🏋️ Athletes: High muscle mass skews results
  • 👵 Seniors: Muscle loss masks risks
  • 🧒 Children: Use pediatric growth charts

Try our body fat calculator for precision.

Pets use a Body Condition Score (BCS) system (1-9 scale):

  • 1-3: Underweight
  • 4-5: Ideal weight
  • 6-9: Overweight

Our pet BMI tool includes breed-specific guidance.

Consult a doctor if:

  • BMI < 18.5 or > 30
  • Waist > 40" (men) or 35" (women)
  • Symptoms like fatigue or shortness of breath

Yes! Our advanced BMI calculator accounts for muscle mass and suggests body fat % for athletes.

Absolutely. Our BMI tracker helps you:

  • Set realistic weight goals
  • Track progress with charts
  • Get personalized diet/exercise tips

Yes! Our teen BMI tool uses:

  • Age and gender percentiles
  • CDC growth chart standards
  • Healthy range comparisons

High BMI increases risks of:

  • Heart disease
  • High blood pressure
  • Type 2 diabetes

Our calculator flags risk thresholds automatically.

Yes! Our dog BMI tool adjusts for:

  • Breed size (Chihuahua vs. Labrador)
  • Age-specific weight ranges
  • Activity level considerations

No data is stored or shared. Our tool:

  • Processes calculations locally in your browser
  • Has no tracking cookies
  • Requires no signup

Signs of feline overweight:

  • Can't feel ribs under fat layer
  • No visible waist when viewed from above
  • Hanging belly pouch

Use our cat BMI checker for analysis.

Yes, due to:

  • Muscle loss (sarcopenia) after 40
  • Metabolic rate changes
  • Hormonal shifts

Our calculator provides age-adjusted guidance.

Standard ranges:

  • Underweight: < 18.5
  • Healthy: 18.5–24.9
  • Overweight: 25–29.9
  • Obese: ≥ 30

We provide personalized interpretations.

Yes! Generate a printable PDF with:

  • Your BMI trajectory
  • Diet/exercise recommendations
  • Doctor discussion notes

Overweight dogs are prone to:

  • Arthritis
  • Hip dysplasia
  • ACL tears

Our pet health analyzer flags these risks.

About SmartBMIcalc

Your trusted partner for human and pet health insights

Our Health Philosophy

At SmartBMIcalc, we transform complex health metrics into actionable knowledge. Founded in 2023, our platform has helped over 500,000 users understand their weight health through accurate, research-backed tools.

Unlike basic calculators, we provide complete health profiles - combining BMI analysis with personalized recommendations for humans and pets, because wellness knows no species.

Why 500,000+ Users Trust Us

  • Medical-Grade Accuracy: Formulas validated against WHO and NIH standards
  • Expert-Reviewed: Content overseen by licensed nutritionists
  • Privacy First: Your data never leaves your device
  • Pet-Specific: Breed-adjusted calculations for dogs/cats

Our Core Promise

We deliver medical-grade health tools completely free - now and forever. No subscriptions, no hidden fees, just accurate health insights.

Your health data never leaves your device. We believe privacy is fundamental to trustworthy health tools.

The same rigorous standards apply to our pet health tools, with breed-specific calculations you can trust.

For informational use only. Consult healthcare providers for medical advice.

Contact Us

Have questions or feedback? We'd love to hear from you

Disclaimer

The SmartBMIcalc is provided for informational and educational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment.

The BMI calculation is a screening tool and does not directly measure body fat or account for factors such as muscle mass, bone density, age, sex, ethnicity, or individual physical differences. A high or low BMI should be followed by further assessments by a healthcare professional.

Similarly, the pet body condition score (BCS) calculator provides an estimate based on limited information and should not replace a proper veterinary examination. Different breeds and individual animals may have different healthy weight ranges.

Always consult with qualified healthcare providers or veterinarians regarding any health-related questions or decisions about diet, exercise, or medical treatments for yourself or your pets.

Privacy Policy

Your privacy is important to us. The SmartBMIcalc operates entirely within your browser. We do not collect, store, or share any of your personal health information or calculation results.

When you use our calculator, all data processing occurs locally on your device. None of your measurements, BMI results, or other health information is transmitted to our servers or any third parties.

The PDF reports generated by our tool are created and downloaded directly to your device without passing through our servers.

For more information about our privacy practices, please contact us using the form above.