20-20-20 Eye Strain Relief Timer Calculator
Free eye strain calculator using the 20-20-20 rule. Find your optimal break schedule and total break time needed for your daily screen exposure.
A1C Calculator
Convert A1C to average blood sugar and back. Diabetes lab result calculator. Free A1C converter.
BAC Calculator (Blood Alcohol)
Estimate your blood alcohol concentration (BAC) based on drinks, weight, sex, and time. See when you will be sober. Free BAC calculator.
Biological Age Estimator
Free biological age calculator. Estimate your body's functional age based on exercise, sleep, diet, stress, and health habits.
Blood Pressure Calculator
Check your blood pressure category and risk level. AHA guidelines with recommendations. Free BP calculator.
Blue Light Sleep Delay Calculator
Free blue light sleep calculator. Estimate how much your evening screen exposure is delaying melatonin production and pushing back your natural sleep time.
BMI Calculator
Free BMI calculator. Enter height and weight to get your BMI, weight category (underweight/normal/overweight/obese), and healthy weight range.
BMR Calculator
Free BMR calculator using the Mifflin-St Jeor equation. Find your Basal Metabolic Rate and understand your base calorie needs.
Breathwork Pattern Calculator
Free breathwork calculator. Calculate cycle timing, total session duration, and breath counts for box breathing (4-4-4-4), 4-7-8 breathing, and custom patterns.
Caffeine Half-Life & Sleep Timer
Free caffeine half-life calculator. Find how much caffeine remains in your system at any hour and calculate your ideal last-coffee time for quality sleep.
Calorie Calculator
Free TDEE calorie calculator using the Mifflin-St Jeor equation. Find your Total Daily Energy Expenditure for weight loss, maintenance, or muscle gain.
Calorie Deficit Calculator
Free calorie deficit calculator. Find your daily calorie target for any weight loss rate — safe deficit, time to goal, and weekly loss projection.
Dental Cost Calculator
Estimate dental procedure costs with and without insurance. Common treatments priced. Free dental calculator.
GLP-1 / Ozempic Cost Calculator
Calculate GLP-1 medication costs. Ozempic, Wegovy, Mounjaro pricing with and without insurance coverage.
Grip Strength Longevity Percentile Calculator
Assess your grip strength by age and gender. See percentile ranking and health risk correlation. Free calculator.
High Altitude Water Intake Calculator
Free high altitude water intake calculator. Find your increased hydration needs at elevation due to increased respiration rate and lower humidity.
HRV Meaning Interpreter
Free HRV calculator. Interpret your morning HRV score from Whoop, Garmin, or Apple Watch — what it means for recovery and whether to train hard or rest.
Ideal Body Weight Calculator
Free ideal body weight calculator using the Devine, Robinson, Miller, and Hamwi formulas. Find your ideal weight range based on height and sex.
Intermittent Fasting Window Calculator
Free intermittent fasting calculator. Plan your 16:8, 18:6, 20:4, or 5:2 fasting schedule with eating windows and fasting end times.
Macro Calculator (Protein, Carbs, Fat)
Calculate daily macronutrients — protein, carbs, and fat grams — based on your calories and fitness goal. For weight loss, muscle gain, or maintenance.
Magnesium Dosage Calculator
Free magnesium dosage calculator. Find your recommended daily magnesium intake based on body weight, age, and biological sex following RDA guidelines.
Medicare Cost Calculator
Calculate total Medicare premiums and costs by income. Parts A, B, D, and Medigap. Free Medicare calculator.
Pickleball Calories Burned Calculator
Calculate calories burned playing pickleball by weight, duration, and intensity. Based on peer-reviewed MET values. Free pickleball calorie calculator.
Pregnancy Due Date Calculator
Calculate your pregnancy due date from your last period or conception date. See trimester breakdown, key milestones, and week-by-week timeline.
Protein Intake Calculator
Calculate your optimal daily protein intake based on weight, activity, and goal. For weight loss, muscle building, or general health.
Sleep Calculator
Calculate optimal sleep and wake times based on 90-minute sleep cycles. Find the best bedtime to wake up refreshed. Free sleep cycle calculator.
Standing Desk Time Ratio Calculator
Free standing desk calculator. Find your ideal sitting vs standing ratio and schedule based on your work hours and health goals.
TDEE Calculator (Total Daily Energy Expenditure)
Calculate your TDEE (Total Daily Energy Expenditure). BMR + activity level = daily calorie burn. For weight loss, muscle gain, or maintenance.
Vitamin D Sunlight Calculator
Free Vitamin D calculator. Estimate daily sun exposure needed for adequate Vitamin D synthesis based on latitude, skin tone, season, and time of day.
VO2 Max & Longevity Calculator
Estimate your VO2 max from a run test and see the longevity correlation. Based on peer-reviewed research linking cardiorespiratory fitness to lifespan.
Water Intake Calculator
Free water intake calculator. Find your recommended daily water intake in oz, cups, and liters based on weight and exercise.
Water Intake Calculator
Calculate daily water intake by weight and activity. Personalized hydration recommendation. Free calculator.
Understanding Your Health Numbers
Your doctor gives you numbers at every visit — blood pressure, BMI, A1C, cholesterol — but understanding what they mean and how to improve them is where real health improvement begins. These calculators help you interpret your results, set realistic goals, and track progress over time. Every formula is sourced from clinical guidelines used by medical professionals.
Calculators Are Tools, Not Diagnoses
These calculators provide general health information based on established medical formulas. They are educational tools — not diagnostic instruments. Always consult your healthcare provider for personal medical advice, especially before making significant changes to diet, exercise, or medication. Your doctor knows your complete medical history and can provide guidance tailored to your specific situation.
Frequently Asked Questions
Can I trust these health calculators?▾
The formulas are sourced from WHO, NIH, and peer-reviewed research — the same references your doctor uses. However, calculators provide general estimates, not personalized medical advice. Individual factors (genetics, medications, conditions) affect your specific numbers. Use these as educational tools and discuss results with your healthcare provider.
Which health calculator is most important?▾
BMI and Blood Pressure calculators address the two most common health screenings. The Calorie Calculator is essential for anyone managing their weight. For diabetics, the A1C Calculator helps interpret lab results. Start with whichever metric your doctor has flagged for attention.