There are two units of measurement for blood glucose level. In the U.S., blood glucose level is noted in milligrams per deciliter, or mg/dl, which is a unit used in medicine to measure the concentration of substances in the blood. Other areas of the world, specifically Europe, use the Systeme International unit of millimoles per liter, or mmol/L, to express blood concentrations. To convert from one unit to another requires only a simple mathematical conversion.

Step 1

Get your blood glucose tested by your health-care professional, or use a home monitoring device.

 Step 2

Multiply your blood glucose value in mmol/L by 18, since 1 mmol/L equals 18 mg/dl. For example, if your value is 5 mmol/L, multiply 5 by 18 to give you a blood glucose value of 90 mg/dl.

Step 3

Round the mg/dl value to the nearest whole number, if needed. For example, if your value is 35.5 mg/dl, simply state the value as 35 mg/dl.

Step 4

If you want to check your work or do the reverse conversion, divide your mg/dl result by 18 to give mmol/l.