Blood Sugar Converter

Divide the mg/dL value by 18.0182 to get mmol/L. For example, 100 mg/dL divided by 18.0182 is about 5.55 mmol/L. To go the other way, multiply the mmol/L value by 18.0182, so 7.0 mmol/L times 18.0182 is about 126 mg/dL.

It comes from the molar mass of glucose (180.156 grams per mole) divided by 10, because a deciliter is one tenth of a liter. The result, 18.0182, is the standard factor used by the American Diabetes Association, the WHO, and clinical labs to switch between the two units.

The United States, Germany, Japan, and a few others report blood glucose in mg/dL. Most other countries, including the United Kingdom, Canada, and Australia, use mmol/L. This converter lets you read a value in whichever unit your meter or lab uses.

For fasting glucose, a normal level is 70 to 99 mg/dL (3.9 to 5.5 mmol/L). Prediabetes is 100 to 125 mg/dL (5.6 to 6.9 mmol/L), and the diabetes range is 126 mg/dL (7.0 mmol/L) or higher. A value below 70 mg/dL (3.9 mmol/L) is considered low. A single reading is not a diagnosis.

The unit conversion itself is the same for any reading, since it only changes the unit, not the value. The category labels shown here use fasting glucose thresholds, so post-meal or random readings will not map to the same categories. Use the converted number, not the category, for non-fasting values.

No. This converter is for education and general reference only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss your blood sugar results and any treatment decisions with a qualified healthcare provider.