Lab units · glucose
Blood sugar converter, mg/dL to mmol/L.
Type a glucose reading in either unit and see the other one. The US reports mg/dL; Canada, the UK, Australia and most of Europe report mmol/L. This tool only changes the unit.
Convert a glucose value
Result
Enter a glucose value in either box.
How the conversion works
Glucose has a molar mass of 180.16 g/mol. A reading in mg/dL is milligrams per 100 mL, so it is multiplied by 10 to get mg/L and then divided by 180.16 to get mmol/L. In one step: mmol/L = mg/dL ÷ 18.016, or about × 0.0555. Going back, mg/dL = mmol/L × 18.016. Many meters and charts round the factor to 18, which can differ from the exact result by a few tenths of a percent.
Worked example
A reading of 100 mg/dL is 100 ÷ 18.016 = 5.55 mmol/L. A reading of 7.0 mmol/L is 7.0 × 18.016 = 126 mg/dL.
Conversion chart
Both tables use the exact factor and are rounded to the precision shown.
| mg/dL | mmol/L |
|---|---|
| 54 mg/dL | 3 mmol/L |
| 70 mg/dL | 3.89 mmol/L |
| 90 mg/dL | 5 mmol/L |
| 100 mg/dL | 5.55 mmol/L |
| 126 mg/dL | 6.99 mmol/L |
| 140 mg/dL | 7.77 mmol/L |
| 180 mg/dL | 9.99 mmol/L |
| 200 mg/dL | 11.1 mmol/L |
| 250 mg/dL | 13.88 mmol/L |
| 300 mg/dL | 16.65 mmol/L |
| 400 mg/dL | 22.2 mmol/L |
| mmol/L | mg/dL |
|---|---|
| 3 mmol/L | 54 mg/dL |
| 4 mmol/L | 72.1 mg/dL |
| 5 mmol/L | 90.1 mg/dL |
| 6 mmol/L | 108.1 mg/dL |
| 7 mmol/L | 126.1 mg/dL |
| 8 mmol/L | 144.1 mg/dL |
| 10 mmol/L | 180.1 mg/dL |
| 12 mmol/L | 216.2 mg/dL |
| 15 mmol/L | 270.2 mg/dL |
| 20 mmol/L | 360.3 mg/dL |
Sources
Molar mass from the NIH PubChem record for glucose. The mg/dL-to-mmol/L relationship is the standard SI conversion used in laboratory reporting. TNAADO checked the factor against its own arithmetic on 4 October 2026.
Frequently asked questions
How do I convert mg/dL to mmol/L?
Divide the mg/dL figure by 18.016. For example 180 mg/dL is 180 ÷ 18.016 = 10.0 mmol/L.
How do I convert mmol/L to mg/dL?
Multiply the mmol/L figure by 18.016. For example 5.5 mmol/L is 5.5 × 18.016 = 99.1 mg/dL.
Why do some sites use 18 instead of 18.016?
18 is a convenient rounding of the glucose molar-mass factor. It changes results by well under one percent, which is smaller than the error of most home meters.
Does this tell me whether my reading is normal?
No. Targets and reference intervals depend on the test (fasting, random, after a meal), your age, pregnancy and any treatment plan. This page only converts units. Ask your clinician or the reporting laboratory.
Reference information, not medical advice
This page converts units only. It does not interpret a result, and units and reference intervals differ between laboratories. Ask the clinician who ordered the test or the reporting laboratory what a result means for you. If you are worried about a result or symptoms, contact a health professional; in an emergency call your local emergency number.