ASCVD 10-year risk
Free ASCVD risk calculator using the ACC/AHA Pooled Cohort Equations to estimate your 10-year risk of heart attack or stroke, for adults aged 40 to 79.
Health Calculators
Free, evidence-based health assessment tools.
Heart and blood pressure
LDL cholesterol
Calculate LDL cholesterol from your lipid panel with the NIH Sampson equation, accurate up to triglycerides of 800, plus Friedewald and LDL categories.
Mean arterial pressure (MAP)
Enter your blood pressure for an instant MAP. Normal is 70 to 100 mmHg. Includes the formula and a chart of MAP for common readings, like 120/80 = 93.
QTc interval
Correct QT for heart rate with Framingham, Bazett and Fridericia. Prolonged is 450 ms or more in men, 460 in women; above 500 ms is high risk.
CHA2DS2-VASc (AFib stroke risk)
Free CHA2DS2-VASc calculator to estimate stroke risk in atrial fibrillation and help guide whether anticoagulation is recommended. Runs in your browser.
Heart rate zones
Estimate your max heart rate with the Tanaka formula (208 − 0.7 × age) and your light, moderate and vigorous target heart rate zones, with a chart by age.
Body size and metabolism
BMI and goal weight
Interactive BMI calculator with dual modes: calculate your current BMI or determine target weight for your goal BMI. Supports both metric and imperial units with instant conversions.
Body fat (US Navy method)
Estimate body fat percentage with the US Navy tape-measure method, then compare it with published healthy ranges for your age, sex and ancestry.
Waist-to-height ratio
Free waist-to-height ratio calculator. A simple central-fat measure that often predicts cardiometabolic risk better than BMI. Runs in your browser.
Ideal body weight
Devine formula: men 50 kg and women 45.5 kg, plus 2.3 kg per inch over 5 feet. Calculate ideal body weight in kg and lb, with a chart by height.
TDEE and BMR
Free TDEE and BMR calculator using the Mifflin-St Jeor equation to estimate your daily calorie needs from height, weight, age, sex, and activity level.
Body surface area
Calculate body surface area (BSA) in m² from height and weight with the Mosteller formula, plus DuBois for comparison, and a BSA chart by height and weight.
Blood sugar and insulin
A1c to average glucose
Convert your A1c to estimated average glucose in mg/dL and mmol/L, and see your ADA category. Includes an A1c to glucose chart from 5% to 12%.
HOMA-IR (insulin resistance)
Calculate HOMA-IR from fasting glucose and insulin. Under 2.0 is typical of healthy adults; 2.7 or above suggests insulin resistance. Includes a lookup chart.
Kidney and blood chemistry
eGFR (CKD-EPI 2021)
Free eGFR calculator using the 2021 race-free CKD-EPI creatinine equation to estimate kidney function and KDIGO stage from your serum creatinine, age, and sex.
Creatinine clearance (Cockcroft-Gault)
Estimate creatinine clearance (CrCl) for renal drug dosing with the Cockcroft-Gault equation. Accepts mg/dL or µmol/L. Includes the formula and an example.
Anion gap
Calculate the anion gap from sodium, chloride and bicarbonate, with an optional albumin correction. Typical range is about 3 to 11 mEq/L on modern analyzers.
Corrected calcium
Correct total calcium for albumin instantly. Formula: calcium + 0.8 × (4.0 - albumin). Includes a quick chart, a worked example and the mmol/L version.
Liver
FIB-4 liver fibrosis score
Calculate the FIB-4 liver fibrosis score from age, AST, ALT and platelets. Below 1.3 is low risk; 2.67 or above is high. Includes the age 65+ cut-off.
MELD 3.0
Calculate MELD 3.0, the score OPTN uses to rank adults for liver transplant, from bilirubin, sodium, INR, creatinine, albumin and sex, with worked examples.
Mental health and brain
PHQ-2 depression pre-screen
Free PHQ-2 depression pre-screen. Answer two questions to see whether a full PHQ-9 is worth completing. Runs entirely in your browser.
PHQ-9 depression score
Answer the 9 PHQ-9 questions to get your depression score (0 to 27) and severity, from minimal to severe. Private and runs entirely in your browser.
GAD-7 anxiety score
Free GAD-7 calculator to screen for and grade generalized anxiety. Answer 7 questions to get your score and severity, entirely in your browser.
Glasgow Coma Scale
Score the Glasgow Coma Scale from eye, verbal and motor responses using the official descriptors. Mild is 13 to 15, moderate 9 to 12, severe 3 to 8.
Lungs and cancer screening
Pack-years and lung screening
Calculate smoking pack-years and check if you qualify for lung cancer screening: age 50 to 80 with 20+ pack-years under USPSTF 2021 and ACS 2023 guidance.