How to Use the Blood Glucose Unit Converter
Enter a blood glucose value and select the unit (mg/dL or mmol/L). The converter instantly shows the equivalent in the other unit and provides an ADA-based fasting blood glucose assessment for quick reference. This tool is for informational purposes only and does not replace medical advice.
Conversion Formula
mmol/L = mg/dL ÷ 18.0182. This factor comes from the molecular weight of glucose (180.18 g/mol). Examples: 70 mg/dL = 3.9 mmol/L (low boundary), 100 mg/dL = 5.6 mmol/L (normal limit), 126 mg/dL = 7.0 mmol/L (diabetes threshold), 180 mg/dL = 10.0 mmol/L (post-meal target upper limit for diabetics).
Units by Country
The United States and Japan use mg/dL. The United Kingdom, Canada, Australia, and most European countries use mmol/L. When reading CGM devices or glucometers from different regions, or international diabetes management guidelines, always verify the unit first.
Fasting vs. Post-Meal Levels
Fasting blood glucose is measured after at least 8 hours without eating. Post-meal (2-hour postprandial) target is below 140 mg/dL (7.8 mmol/L) for non-diabetics. For people managing diabetes, the ADA targets are: fasting 80–130 mg/dL, and post-meal below 180 mg/dL.
Frequently Asked Questions
Blood glucose is a snapshot at a specific moment. HbA1c reflects average blood glucose over the past 2–3 months. An HbA1c of 6.5% or higher indicates diabetes. This converter only handles the mg/dL ↔ mmol/L unit conversion for glucose readings.
Home glucometers test capillary (finger-prick) whole blood, which can read 10–15% higher than venous plasma used in lab tests. For diagnostic purposes, always rely on laboratory blood draws performed by healthcare professionals.