Blood sugar converter: mg/dL to mmol/L

How to convert mg/dL to mmol/L

Divide the mg/dL value by 18. To go the other way, multiply mmol/L by 18.

• 100 mg/dL ÷ 18 = 5.6 mmol/L
• 7.0 mmol/L × 18 = 126 mg/dL

The exact factor is 18.016, which comes from the molar mass of glucose (180.16 g/mol). Meters, sensors and the Dulce app round it to 18, so this converter uses 18 too and the numbers match what you see every day. At normal glucose levels the difference is never more than 0.1 mmol/L.

Why there are two units

It depends on where you live. The United States, Spain, most of Latin America, Germany, France and Italy use mg/dL. The UK, Ireland, Canada, Australia and the Nordic countries use mmol/L. If you read a British forum or study, you will almost certainly see mmol/L.

Common values

mg/dL	mmol/L	What it usually means
54	3.0	Level 2 hypoglycemia (act now below this)
70	3.9	Bottom of the target range
100	5.6	Upper limit of normal fasting glucose (without diabetes, below this)
140	7.8
180	10.0	Top of the target range
250	13.9	Above this: level 2 hyperglycemia
300	16.7

The 70 and 180 mg/dL (3.9 and 10.0 mmol/L) limits come from the international consensus on time in range. Your care team may set different targets for you.

In Dulce you don't need to convert

In Settings → Glucose unit you can choose mg/dL or mmol/L. The home screen, Lock Screen, Apple Watch and alerts all switch together.

Sources

• Battelino T. et al. Clinical Targets for Continuous Glucose Monitoring Data Interpretation. Diabetes Care 2019;42:1593-1603. doi.org/10.2337/dci19-0028
• American Diabetes Association. Standards of Care in Diabetes. professional.diabetes.org/standards-of-care

This article is for information and does not replace advice from your care team. Dulce is not a medical device and does not replace your sensor's alarms.