All Health Calculators
This is the full library of our free health calculators, every tool runs instantly in your browser, and nothing you enter is ever stored or shared. From checking your BMI or blood pressure to estimating kidney function and daily protein needs, each calculator is built on the same clinically accepted formulas used in real medical practice.
Health π§¬
BMI Calculator
Check your BMI in seconds with our free BMI calculator. See your weight category, healthy weight range, and what your number really means for your health.
Health βChronological Age Calculator
Free chronological age calculator. Enter your date of birth to get your exact age in years, months & days. Private, instant, works for any date.
Health βGFR Calculator
Free GFR calculator estimates your kidney function using creatinine, cystatin C, or both (CKD-EPI 2021 & 2012). See your eGFR and CKD stage instantly.
Health βMAP Calculator
Use our free MAP calculator to calculate mean arterial pressure (MAP) from any bp reading with standard formula, and plain-language interpretation.
Health βCorrected Calcium Calculator
Calculate albumin-corrected calcium with the (Payne formula) for hypoalbuminemia. Adjust total serum calcium in mg/dL or mmol/L. Free, instant, no sign-up.
Health βWater Intake Calculator
Free water intake calculator. Get your daily hydration goal in oz, cups & bottles, adjusted for your weight, age, activity, and climate.
Health βA1C Calculator
Free A1C Calculator, convert HbA1c to estimated average glucose (eAG), check diabetes risk, understand A1C ranges, and get ADA-based guidance.
Health βFitness πͺ
Army Body Fat Calculator (2026 WHtR Standard)
The Army body fat test changed on July 7, 2026. Calculate your official Waist-to-Height Ratio and see if you meet the new under-0.55 standard.
Fitness βBody Fat Calculator
Estimate your body fat percentage free using the U.S. Navy, RFM, skinfold, or BMI method. Get fat mass, lean mass, and your waist-to-height ratio instantly.
Fitness βBench Press Calculator
Estimate your bench press 1RM with the Epley formula, get training percentages, and see how your strength compares to real lifter data. Free and instant.
Fitness βNavy Body Fat Calculator
The Navy replaced its tape test in 2026. Run the official two-step BCA: waist-to-height screening plus body fat, with the max waist for your height.
Fitness βNutrition π₯
Starbucks Calorie Calculator
Free Starbucks calorie calculator for 61 US drinks. Check calories, sugar, caffeine and protein for any order, with milk swaps, pumps and cold foam.
Nutrition βProtein Calculator
Find your daily protein target by weight, activity, and goal. Free protein calculator built on the 2025β2030 Dietary Guidelines. Instant, private results.
Nutrition βWhy Use Our Health Calculators?
Health Calculator exists because checking a health number shouldn't require an account, an app download, or handing over your personal data. Every tool on this page runs locally in your browser β we never see, store, or share what you enter.
Accuracy gets the same treatment a clinic would give it. Our calculators are built on published clinical standards: the race-free CKD-EPI 2021 equation for GFR, the ADA's eAG conversion for A1C, the Payne formula for corrected calcium, and WHO ranges for BMI. When guidelines change, we update the tools.
New calculators are added regularly across health, fitness, and nutrition. If there's one you'd like to see next, tell us through the contact page β reader requests decide what we build next.
These tools are for education, not diagnosis. Always discuss unusual results with a healthcare professional.