Health

Blood Sugar Converter

Convert blood sugar between mg/dL and mmol/L instantly in either direction using the glucose factor of 18.0182.

Blood Sugar Converter

mg/dL

mmol/L

Method

How this calculator works

mmol/L = mg/dL / 18.0182 and mg/dL = mmol/L × 18.0182, where 18.0182 is the glucose-specific conversion factor derived from its molar mass.

Type a value into either the mg/dL field or the mmol/L field.
To convert mg/dL to mmol/L, the tool divides your number by 18.0182.
To convert mmol/L to mg/dL, it multiplies your number by 18.0182.
The opposite field updates instantly as you type, so you never overwrite your own entry.

Examples

Worked examples

Real numbers, end-to-end results.

100 mg/dL

= 5.6 mmol/L

100 ÷ 18.0182 = 5.55 mmol/L.

7.0 mmol/L

= 126 mg/dL

7.0 × 18.0182 = 126.1 mg/dL, a common fasting-diabetes threshold.

180 mg/dL

= 10.0 mmol/L

180 ÷ 18.0182 = 9.99 mmol/L.

Use cases

When to use it

Comparing glucose readings between US and international meters or labs.
Interpreting research papers or clinical guidelines that use the other unit.
Helping travelers and expatriates understand local blood-sugar numbers.
Teaching students the relationship between mg/dL and mmol/L.

Disclaimer: This calculator provides estimates for informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for decisions affecting your health. Results depend on the accuracy of inputs provided.

FAQ

Frequently asked questions

What is the difference between mg/dL and mmol/L?

They are two units for the same thing: the concentration of glucose in blood. mg/dL (milligrams per deciliter) is used mainly in the United States, while mmol/L (millimoles per liter) is the standard in most of the rest of the world. The conversion factor for glucose is 18.0182.

How do I convert mg/dL to mmol/L?

Divide the mg/dL value by 18.0182. For example, 100 mg/dL ÷ 18.0182 ≈ 5.6 mmol/L. To go the other way, multiply the mmol/L value by 18.0182.

Why is the conversion factor 18.0182?

It comes from the molar mass of glucose (about 180.16 g/mol). Converting mg/dL to mmol/L requires dividing by the molar mass and adjusting for the deciliter-to-liter difference, which works out to a factor of 18.0182 for glucose specifically.

What are normal blood sugar ranges?

For most adults without diabetes, a fasting glucose of 70–99 mg/dL (3.9–5.5 mmol/L) is considered normal. Values are informational only—target ranges vary by individual, time of day, and medical guidance.

Does this converter work for other lab values?

No. The factor 18.0182 is specific to glucose because it depends on glucose's molecular weight. Other blood tests, such as cholesterol or creatinine, use different conversion factors.