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Calculators

Health & lab calculators.

Quick, free calculators for common lab and health numbers — using standard published equations, with a plain-English explanation of what the result means. General education, not medical advice.

eGFR Calculator

Estimate kidney function from your creatinine using the 2021 CKD-EPI equation, and see the KDIGO stage.

A1c to Average Glucose Converter

Convert an HbA1c to an estimated average blood glucose (eAG), in mg/dL and mmol/L — and back again.

LDL Cholesterol Calculator

Calculate LDL (Friedewald) and non-HDL cholesterol from your total cholesterol, HDL, and triglycerides.

Heart Disease Risk Calculator (ASCVD)

Estimate your 10-year risk of heart attack or stroke with the ACC/AHA Pooled Cohort Equations, from your age, cholesterol, blood pressure, and history.

BMI Calculator

Calculate your body mass index from height and weight, in metric or imperial units, with the standard category.

Looking for what a specific test means? See the lab test glossary.

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