mg/dL ↔ mmol/L with category.. Blood Sugar Converter is a free online tool from the ToolsRift Finance & Health Calculators collection. It runs entirely in your browser — nothing to install, no signup, and your data never leaves your device.
Enter a glucose value in either mg/dL or mmol/L. The calculator converts it to the other unit and shows the general category for the reading.
Divide the mg/dL value by 18 to get mmol/L, and multiply mmol/L by 18 to go back. For example, 90 mg/dL equals 5.0 mmol/L.
The United States and a few others report glucose in mg/dL, while most of the world uses mmol/L. Converting lets you compare readings from different sources.
Fasting glucose is often considered normal around 70–99 mg/dL (3.9–5.5 mmol/L), but targets vary by person. Always confirm ranges with your doctor.