🩸 Blood Sugar Converter (mg/dL ↔ mmol/L)
Blood glucose in mg/dL ÷ 18.0182 gives mmol/L; mmol/L × 18.0182 gives mg/dL — this converts either direction exactly. Enter your values below — results update instantly, entirely on your device.
140 mg/dL ÷ 18.0182
How the blood sugar converter (mg/dl ↔ mmol/l) works
mmol/L = mg/dL ÷ 18.0182, and mg/dL = mmol/L × 18.0182. The factor is the molar mass of glucose (180.156 g/mol) divided by 10, because mg/dL and mmol/L differ by both the molar mass and the dL→L (×10) volume unit.
Example: 140 mg/dL ÷ 18.0182 = 7.8 mmol/L. Going the other way, 7 mmol/L × 18.0182 = 126 mg/dL.
Two conventions for the same measurement: the United States, Germany and a few others report glucose in mg/dL, while the UK, Canada, Australia and most of the world use mmol/L. The 18.0182 conversion factor is exact (glucose molar mass ÷ 10), so no accuracy is lost. This tool is for converting units only — it is not medical advice and does not interpret whether a reading is high or low; discuss targets with your clinician.
Frequently asked questions
How do I convert mg/dL to mmol/L?
Divide by 18.0182. For example 100 mg/dL ÷ 18.0182 = 5.6 mmol/L. To go back, multiply mmol/L by 18.0182.
Why is the factor 18.0182?
It is the molar mass of glucose (180.156 g/mol) divided by 10. The ÷10 accounts for mg/dL using decilitres while mmol/L uses litres, and the molar mass converts milligrams to millimoles.
Which countries use which unit?
The US, Germany, Japan (partly), and a few others use mg/dL; the UK, Canada, Australia, and most of Europe use mmol/L. HbA1c uses different units again.
Is a reading of 7 mmol/L normal?
This tool only converts units and does not interpret readings — what counts as normal depends on the person, the time of day and whether you have eaten. Always discuss your numbers with a healthcare professional.
Is my reading kept private?
Yes. The conversion runs entirely in your browser; nothing you type is sent anywhere.
Is this blood sugar converter (mg/dl ↔ mmol/l) accurate and private?
Yes. It uses the standard published formula, shows its working under every result, and computes locally in your browser — your inputs are never sent to a server, and the page works offline.