This blood sugar converter changes a glucose result between milligrams per deciliter (mg/dL) and millimoles per liter (mmol/L). Enter the number exactly as it appears on a glucose meter, continuous glucose monitor report, laboratory result or care plan, then choose the direction. The calculation happens in your browser. Nothing you enter is sent to osvilt.com.
Blood glucose unit converter
Choose the unit on the result you have, enter its value, and select Convert.
Blood glucose conversion table
This quick table gives common glucose values in both unit systems. It is a unit reference only. A number that is expected before a meal may mean something different after food, exercise, alcohol, illness, pregnancy or a medicine change.
| mg/dL | mmol/L |
|---|---|
| 40 | 2.2 |
| 54 | 3.0 |
| 70 | 3.9 |
| 80 | 4.4 |
| 90 | 5.0 |
| 100 | 5.5 |
| 110 | 6.1 |
| 126 | 7.0 |
| 140 | 7.8 |
| 154 | 8.5 |
| 180 | 10.0 |
| 200 | 11.1 |
| 250 | 13.9 |
| 300 | 16.6 |
| 400 | 22.2 |
Keep the context with the number. Write down when you tested, whether you had eaten, the device used, symptoms and medicines that may matter. That record is more useful at a clinical visit than a converted number on its own.
How to convert blood sugar units
To change a glucose result from mg/dL to mmol/L, multiply it by 0.0555. To change mmol/L to mg/dL, divide it by 0.0555. For example, 100 mg/dL converts to 5.55 mmol/L, which this page rounds to 5.6 mmol/L. The NIDDK conversion appendix provides a detailed glucose table using this calculation.
Both units describe the concentration of glucose in blood. The unit on a home meter, laboratory report or care plan often reflects local practice. The United States commonly uses mg/dL; mmol/L appears in many other countries and in some international materials. A conversion changes the unit, not the underlying measurement.
How to use a converted result
Start with the unit printed on the original result. A 100 on a meter set to mg/dL does not mean the same thing as a 100 on a meter set to mmol/L. Confirm the unit in the device settings or instruction booklet before converting. When a device displays LO, HI or an error code, use the device instructions and your personal care plan rather than trying to calculate a number.
For people with diabetes, glucose targets are individualized. Age, pregnancy, diabetes type, medicines, risk of hypoglycemia and other health conditions can affect the plan. The American Diabetes Association advises people to discuss their own checking schedule and target range with their care team. A conversion page should not replace a written plan for insulin, food, exercise or sick days.
Why a meter, CGM and laboratory result may differ
A finger-stick meter measures a small blood sample at one moment. A continuous glucose monitor estimates glucose in fluid between cells, while a laboratory glucose test uses a laboratory method. They serve related purposes, yet they are not interchangeable in every situation. Compare like with like when tracking a trend.
Technique and equipment also matter. The FDA advises washing and drying hands, using the correct unexpired strips for the meter, and following the device instructions. Food or sugar on fingers, damaged strips, poor storage and an incorrect testing method can affect a home result. A number that does not fit how you feel deserves attention, especially when a meter reports an unexpected extreme.
When to get help for a blood glucose result
Follow your diabetes care plan for high or low readings. Seek urgent medical help for severe confusion, a seizure, fainting, inability to swallow safely, trouble breathing, chest pain, or a person who cannot stay awake. Call emergency services for an emergency rather than waiting for a value to normalize.
Arrange prompt clinical advice when repeated readings fall outside the goals you were given, the device repeatedly shows an error or out-of-range message, or you have symptoms such as unusual thirst, frequent urination, vomiting, shakiness, sweating, dizziness or confusion. People without a diabetes diagnosis should not use a home conversion alone to diagnose diabetes. A clinician can choose the right test and interpret it with the full history.
Frequently asked questions
How many mmol/L is 100 mg/dL?
100 mg/dL converts to 5.55 mmol/L, usually written as 5.6 mmol/L after rounding to one decimal place.
How many mg/dL is 7 mmol/L?
7 mmol/L converts to about 126 mg/dL. The calculator uses the same 0.0555 conversion factor in reverse.
Can this converter tell me whether I have diabetes?
No. It translates a glucose unit. Diagnosis needs an appropriate test and clinical interpretation. A home result can be affected by timing, technique and the device used.
Should I change my meter from mg/dL to mmol/L?
Use the unit specified in your care plan and familiar to your care team. Check the meter manual before changing a setting. Consistency reduces the risk of recording or acting on a number in the wrong unit.
Sources reviewed
- NIDDK: Diabetes in America, Appendix 1 conversions
- American Diabetes Association: Diabetes tests and blood glucose monitoring
- FDA: Blood glucose monitoring devices
- FDA: Safe use of glucose meters and test strips
- MedlinePlus: Blood glucose test
