These calculators cover key cardiovascular metrics — from checking your Cholesterol Ratio and estimating VO2 Max to finding your aerobic training zones with the Target Heart Rate Calculator or the more precise Karvonen Formula version. Clinical tools like the QTc Calculator and Rate Pressure Product Calculator give deeper insight into cardiac workload, while the Estimated Average Glucose Calculator bridges heart and metabolic health.

Browse the most-popular list to see which tools other visitors rely on, or open the Trending tab to see what's gaining attention. Every calculator is free, requires no sign-up, and works on any device.

  • Modified Sgarbossa Criteria Calculator
    Calculate RMSSD heart rate variability from RR intervals. Also returns SDNN, mean RR interval and average heart rate from your beat-to-beat data.
  • Waist Circumference Percentile Calculator
    Check your abdominal-obesity health risk from waist circumference. Men >102cm/40in and women >88cm/35in flag high risk. Free, instant, cm or inches.
  • Creatinine Clearance (IBW) Calculator
    Estimate creatinine clearance (CrCl) with the Cockcroft-Gault equation using age, weight, sex, and serum creatinine. Result in mL/min for renal dosing.
  • Deep Breathing Heart Rate Zone Calculator
    Find your relaxation heart rate zone for deep breathing. Enter your age to get max heart rate and the calming 50–60% target range in bpm.
  • QTc Calculator (Corrected QT Interval)
    Calculate the corrected QT interval (QTc) from QT and heart rate using the Bazett, Fridericia, Framingham, or Hodges correction formulas.
  • Rate Pressure Product Calculator
    Calculate Rate Pressure Product (RPP) instantly: multiply heart rate by systolic blood pressure to estimate myocardial oxygen demand and cardiac workload.
  • Target Heart Rate Zone Calculator
    Find your maximum heart rate and 5 exercise target heart rate zones in bpm using the Basic (%MHR) or Karvonen heart rate reserve method.
  • Heart Rate from RR Interval Calculator
    Convert an ECG RR interval in milliseconds to heart rate in beats per minute (bpm) instantly using HR = 60000 / RR. Free, fast and accurate.
  • Mean Arterial Pressure (MAP) Calculator
    Calculate Mean Arterial Pressure (MAP) from systolic and diastolic blood pressure. MAP = DBP + (SBP − DBP)/3. Instant mmHg result and pulse pressure.
  • Fat-Burning Heart Rate Zone Calculator
    Find your fat-burning heart rate zone (60–70% of max HR) by age. Free calculator using the 220-age formula to estimate your ideal cardio range.
  • Cardio Calorie Burn Calculator
    Estimate calories burned during cardio from your heart rate, weight, age, and duration using the Keytel heart-rate equations for men and women.
  • MAP from Blood Pressure Calculator (DBP + ⅓ Pulse Pressure)
    Calculate Mean Arterial Pressure (MAP) from systolic and diastolic blood pressure using MAP = DBP + (SBP − DBP)/3. Fast, free estimate.
  • Triglyceride to HDL Ratio Calculator
    Calculate your triglyceride to HDL (TG/HDL) ratio from a lipid panel. Enter triglycerides and HDL in mg/dL to assess cardiometabolic risk.
  • Non-HDL Cholesterol Calculator
    Calculate your non-HDL cholesterol by subtracting HDL from total cholesterol. Enter mg/dL values to see your non-HDL level and risk category.
  • Ejection Fraction Calculator (LVEF)
    Calculate left ventricular ejection fraction (LVEF) from end-diastolic and end-systolic volumes. EF% = ((EDV − ESV) / EDV) × 100, with classification.
  • Systemic Vascular Resistance Calculator
    Calculate systemic vascular resistance (SVR) from MAP, CVP and cardiac output. Get results in dynes·s·cm⁻⁵ and Wood units instantly.
  • Creatinine Clearance Calculator (Cockcroft-Gault)
    Estimate creatinine clearance (CrCl) with the Cockcroft-Gault equation using age, weight, sex and serum creatinine. Get mL/min and a kidney function category.
  • Pack-Years Calculator
    Calculate smoking pack-years from cigarettes per day and years smoked. Free tool using the standard pack-years formula for medical screening.
  • Salt to Sodium Converter
    Convert grams of salt to milligrams of sodium instantly. 1 g of salt equals 393.4 mg of sodium — track your daily sodium intake easily.
  • METs to Calories Burned Calculator
    Convert METs to calories burned. Enter activity intensity (METs), body weight, and duration to estimate the energy you expend during exercise.
  • METs to VO2 Conversion Calculator
    Convert METs to VO2 oxygen consumption instantly. Enter activity intensity in METs to get VO2 in mL/kg/min, plus optional absolute VO2 in L/min.
  • Resting Heart Rate Fitness Calculator
    Find your fitness level from your resting heart rate. Compares your RHR against standard age and sex norms to rate it Athlete to Poor.
  • Pulse Pressure Calculator
    Calculate pulse pressure from your blood pressure: Pulse Pressure = Systolic − Diastolic. See if your value is low, normal, or high, plus estimated MAP.
  • Non-HDL Cholesterol Calculator
    Calculate your non-HDL cholesterol by subtracting HDL from total cholesterol (mg/dL). Includes risk category interpretation. Educational use only.

Frequently asked questions

What heart health metrics can these calculators estimate?

You can assess aerobic capacity with the VO2 Max Calculator, find safe training zones with the Target Heart Rate and Karvonen Formula calculators, evaluate cardiac efficiency via the Rate Pressure Product, review cholesterol balance with the Cholesterol Ratio Calculator, and track average glucose levels with the eAG Calculator.

How accurate are the results, and can I use them for clinical decisions?

Tools like the QTc Calculator and Rate Pressure Product Calculator apply standard clinical formulas. However, all outputs are estimates based on your input values — they are NOT a substitute for medical advice or professional diagnosis. Always consult a qualified healthcare professional or clinician before acting on any cardiovascular health information.

What is the Karvonen Formula Target Heart Rate Calculator used for?

It uses your resting heart rate alongside your maximum heart rate to set training zones personalized to your current fitness level — more precise than the basic age-subtracted formula. It's widely used by endurance athletes and personal trainers for structuring cardio sessions at the right intensity.

Do you save any of the health data I enter?

No. Every calculation runs entirely in your browser. Heart rate values, cholesterol numbers, ECG intervals, and any other inputs are never transmitted to our servers or stored between sessions.

Which heart health calculators are used most?

The page is ordered by real visitor usage. Open the Trending tab to see which tools are getting the biggest recent boost in traffic, or the Recently Added tab for the newest tools in the collection.