Lab result interpreter

What is it?

This interpreter lets you choose one of several common tests and enter your result, then shows which reference band it falls into (such as “normal”, “prediabetes” or “within the reference range”), according to its stated source.

All the numbers and ranges here are the same ones already published on the pages of these tests within the encyclopedia, redisplayed here only as a quick calculator.

Why it matters

Knowing the range your result falls in is a useful first step before seeing the doctor, but it does not replace their full interpretation of the result in light of your symptoms and health history.

According to the NIDDK, results such as fasting blood glucose, glycated haemoglobin and OGTT often need a second test on a different day to confirm a diagnosis of diabetes or prediabetes.

How to use it

Choose the test type from the list, then enter your result number in the unit shown (such as mg/dL or % or ml/min/1.73m²), and the corresponding category will appear with its source.

For lipid tests, choose HDL for men or women according to the case, because the reference threshold differs between the sexes in the cited sources.

For glucose tests you can enter the result in mg/dL or mmol/L; mmol/L is converted to mg/dL with the factor NIDDK publishes (mmol/L = mg/dL × 0.0555) before classifying, and the tool shows the value in both units.

For the complete blood count components (haemoglobin, haematocrit and red blood cells), choose the men’s or women’s row, because NHLBI publishes a different range for each; the tool shows whether the result is below, within or above the range.

If your result is outside the "normal" or "optimal" range, do not rely on this general classification alone: see your doctor to interpret it within your full health picture.

Limits of this information

This interpreter covers only a limited number of common tests; many other laboratory tests are not included at all.

Laboratories and national guidelines sometimes differ on exact thresholds. The thresholds here come from NIDDK, CDC, MedlinePlus and the US National Kidney Foundation, and the blood count ranges from NHLBI, which says they vary with sex, age, altitude and race. Your laboratory may use a slightly different reference range, shown on your report.

This tool does not diagnose any disease and does not suggest any treatment or medicine; the treatment programme and the follow-up of the result are decided by the treating doctor.

The eGFR result here is classified only as a ready-made number from your report; to calculate eGFR itself from creatinine, age and sex use the health calculators.

Common questions