Blood Sugar Converter
Blood sugar (glucose) is measured in mg/dL in the United States and mmol/L in most other countries. This converter lets you switch between the two units and shows whether your reading falls in the normal, prediabetes, or diabetic range based on when it was taken.
The conversion between mg/dL and mmol/L uses a fixed factor: divide mg/dL by 18.0182 to get mmol/L, or multiply mmol/L by 18.0182 to get mg/dL. The glucose molecule has a molecular weight of approximately 180.16 g/mol, which is the basis for this conversion.
Understanding your blood sugar numbers matters because interpretation depends heavily on timing. A fasting blood sugar of 110 mg/dL (6.1 mmol/L) falls in the prediabetes range and warrants attention, while the same reading two hours after a large meal would be perfectly normal. That is why doctors specify fasting tests for diabetes screening.
The American Diabetes Association (ADA) defines fasting glucose thresholds as: normal below 100 mg/dL (5.6 mmol/L), prediabetes at 100-125 mg/dL (5.6-6.9 mmol/L), and diabetes at 126 mg/dL (7.0 mmol/L) or higher. For post-meal readings taken 2 hours after eating, the thresholds are: normal below 140 mg/dL (7.8 mmol/L), prediabetes at 140-199 mg/dL (7.8-11.0 mmol/L), and diabetes at 200 mg/dL (11.1 mmol/L) or higher.
DISCLAIMER: This tool is for informational and educational purposes only. Blood sugar classification should be confirmed through clinical testing and interpreted by a qualified healthcare professional. A single reading does not constitute a diagnosis.