Health & Medical Calculators

Free calculators that turn the numbers on a lab report or a health check into the standard scores doctors use. Each page shows the formula, the units it expects, how the result is usually read and its limits. They are for education only and do not replace a consultation with your doctor.

Kidneys

eGFR Calculator (CKD-EPI 2021)Kidney filtration rate from creatinine, age and sex. CKD Stage & KDIGO RiskPlaces eGFR and urine ACR on the KDIGO risk grid. Urine Albumin-Creatinine RatioACR in mg/g from urine albumin and creatinine.

Liver

FIB-4 IndexScreening score for advanced liver fibrosis. APRI ScoreAST-to-platelet ratio for liver scarring. Fatty Liver IndexLikelihood of fatty liver from BMI, waist, triglycerides and GGT.

Blood sugar, lipids and hormones

HbA1c to Average GlucoseConverts HbA1c % to estimated average glucose. HOMA-IRInsulin resistance estimate from fasting insulin and glucose. Cholesterol RatioTotal/HDL, TG/HDL and non-HDL cholesterol. Thyroid Results CheckerTSH, free T4 and free T3 compared with typical ranges. Uric Acid Level CheckerChecks a uric acid result against the usual ranges. Ferritin & Iron StoresReads a ferritin result in context.

Screening, body and nutrition

STOP-BANG Sleep Apnea ScreenThe 8-question screening score for obstructive sleep apnea. BMI CalculatorBody mass index from your height and weight. TDEE CalculatorDaily calorie needs from your activity level. Medical Report Terms ExplainerPlain-English meanings of common lab and report terms.

How to use these calculators safely

  • Check the units. Labs report the same test in different units (for example mg/dL or µmol/L). Each page explains how to convert.
  • Use your lab’s reference range. The ranges printed on your report take priority over typical ranges quoted here.
  • One result is not a diagnosis. Most conditions are diagnosed from repeated tests, symptoms and examination.
  • Never change medicine based on a calculator. Bring the result to your doctor and ask what it means for you.

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