Converting mg/dL to mmol/L is essential when comparing lab results from different countries. The United States uses mg/dL, while most other nations prefer mmol/L.
Our free mg/dL to mmol/L calculator provides instant, accurate conversions for glucose, cholesterol, and other lab values. Simply select your substance, enter your value, and get results with the formula displayed.
mg/dL ⇄ mmol/L Conversion Calculator
2. Understanding mg/dL and mmol/L Units
Medical laboratories measure substances in your blood using specific units. The two most common units for reporting lab results are mg/dL and mmol/L.
mg/dL (milligrams per deciliter) measures the weight of a substance in a specific volume of blood. One deciliter equals 100 milliliters. This unit is standard in the United States, Japan, and a few other countries.
mmol/L (millimoles per liter) measures the number of molecules in a specific volume of blood. This unit is used throughout Europe, Canada, Australia, and most other nations worldwide.
Both units measure the same thing differently. Think of it like measuring distance in miles versus kilometers. The actual distance remains identical, but the number changes based on which system you use.
Understanding both units becomes crucial when reviewing international medical literature. It also matters when using glucose monitors purchased from different countries. Our µmol/L to mg/dL converter handles similar conversions for other lab values.
3. How to Convert mg/dL to mmol/L
Converting mg/dL to mmol/L requires knowing the molecular weight of the substance being measured. Each substance has a unique molecular weight that affects the conversion calculation.
Follow these simple steps:
Select the substance from the dropdown menu above. The calculator automatically loads the correct molecular weight.
Enter your mg/dL value in the input field. The result appears instantly in mmol/L.
Review the formula displayed below the result. This shows exactly how the conversion was calculated.
For the reverse conversion, simply switch to mmol/L to mg/dL mode using the conversion type selector.
4. Conversion Formula Explained
The mg/dL to mmol/L conversion formula uses the substance’s molecular weight. Here is the standard formula:
mmol/L = (mg/dL × 10) ÷ Molecular Weight
Let’s break this down step by step.
First, multiply your mg/dL value by 10. This converts deciliters to liters.
Next, divide by the molecular weight. This converts milligrams to millimoles.
Example with Glucose:
Glucose has a molecular weight of 180.16 g/mol. To convert 100 mg/dL to mmol/L:
mmol/L = (100 × 10) ÷ 180.16
mmol/L = 1000 ÷ 180.16
mmol/L = 5.55
Therefore, 100 mg/dL of glucose equals 5.55 mmol/L.
5. Common Substance Conversion Factors
Different substances require different conversion factors based on their molecular weights. Here are the most commonly tested lab values:
Glucose Molecular Weight: 180.16 g/mol Conversion Factor: Divide mg/dL by 18.016
Cholesterol Molecular Weight: 386.65 g/mol Conversion Factor: Divide mg/dL by 38.665
Triglycerides Molecular Weight: 885.57 g/mol Conversion Factor: Divide mg/dL by 88.557
Urea (BUN) Molecular Weight: 60.06 g/mol Conversion Factor: Divide mg/dL by 6.006
Creatinine Molecular Weight: 113.12 g/mol Conversion Factor: Divide mg/dL by 11.312
Uric Acid Molecular Weight: 168.11 g/mol Conversion Factor: Divide mg/dL by 16.811
For creatinine and uric acid, healthcare providers sometimes use µmol/L instead of mmol/L. Our mg/dL to µmol/L calculator 04 handles these specific conversions.
6. Blood Glucose Conversion Chart
Blood glucose is the most frequently converted lab value. Diabetic patients worldwide need to understand both measurement systems.
| mg/dL | mmol/L | Status |
|---|---|---|
| 70 | 3.9 | Low Normal |
| 80 | 4.4 | Normal |
| 90 | 5.0 | Normal |
| 100 | 5.6 | Normal |
| 110 | 6.1 | Slightly Elevated |
| 126 | 7.0 | Diabetic Threshold (Fasting) |
| 140 | 7.8 | Prediabetic (Post-Meal) |
| 180 | 10.0 | Target Max for Diabetics |
| 200 | 11.1 | Diabetic Threshold (Random) |
| 250 | 13.9 | High |
| 300 | 16.7 | Very High |
| 400 | 22.2 | Dangerously High |
Quick Reference:
Normal fasting glucose: 70-100 mg/dL (3.9-5.6 mmol/L)
Prediabetes range: 100-125 mg/dL (5.6-6.9 mmol/L)
Diabetes diagnosis: 126+ mg/dL (7.0+ mmol/L) fasting
7. Cholesterol Conversion Guide
Cholesterol levels use different target ranges than glucose. Understanding these conversions helps interpret lipid panel results.
| mg/dL | mmol/L | Total Cholesterol Status |
|---|---|---|
| 150 | 3.88 | Optimal |
| 180 | 4.65 | Desirable |
| 200 | 5.17 | Borderline |
| 220 | 5.69 | Borderline High |
| 240 | 6.21 | High |
| 280 | 7.24 | Very High |
LDL Cholesterol Targets:
Optimal: Below 100 mg/dL (2.6 mmol/L)
Near Optimal: 100-129 mg/dL (2.6-3.3 mmol/L)
Borderline High: 130-159 mg/dL (3.4-4.1 mmol/L)
High: 160-189 mg/dL (4.1-4.9 mmol/L)
Very High: 190+ mg/dL (4.9+ mmol/L)
HDL Cholesterol Targets:
Low (Risk Factor): Below 40 mg/dL (1.0 mmol/L)
Acceptable: 40-59 mg/dL (1.0-1.5 mmol/L)
Optimal: 60+ mg/dL (1.6+ mmol/L)
8. Other Lab Value Conversions
Beyond glucose and cholesterol, many other lab values require conversion between units.
Triglycerides
Normal: Below 150 mg/dL (1.7 mmol/L)
Borderline: 150-199 mg/dL (1.7-2.2 mmol/L)
High: 200-499 mg/dL (2.3-5.6 mmol/L)
Very High: 500+ mg/dL (5.7+ mmol/L)
Blood Urea Nitrogen (BUN)
Normal Range: 7-20 mg/dL (2.5-7.1 mmol/L)
BUN measures kidney function and protein metabolism.
Creatinine
Normal Male: 0.7-1.3 mg/dL (62-115 µmol/L)
Normal Female: 0.6-1.1 mg/dL (53-97 µmol/L)
Note that creatinine typically uses µmol/L rather than mmol/L internationally.
Uric Acid
Normal Male: 3.4-7.0 mg/dL (200-420 µmol/L)
Normal Female: 2.4-6.0 mg/dL (140-360 µmol/L)
Calcium
Normal Range: 8.5-10.5 mg/dL (2.1-2.6 mmol/L)
For electrolyte conversions involving milliequivalents, our mEq/L to mmol/L calculator provides accurate results.
9. Why Different Countries Use Different Units
The split between mg/dL and mmol/L has historical roots in medical development.
The United States established its laboratory standards early in the 20th century. American scientists preferred mass-based measurements (mg/dL) because they were straightforward to calculate with available equipment.
European countries later adopted the International System of Units (SI). This system favors molar concentrations (mmol/L) because they better represent chemical reactions in the body.
Neither system is inherently better. Both provide accurate measurements when used correctly.
The World Health Organization recommends mmol/L as the international standard. However, changing established medical practices takes decades. The United States continues using mg/dL due to entrenched systems and training.
This division creates challenges for international medical collaboration. Research papers must often report values in both units. Medical device manufacturers produce different versions for different markets.
10. When to Use This Converter
This mg/dL to mmol/L converter proves valuable in several situations.
Traveling Abroad
If you monitor blood glucose while traveling, local pharmacies may only sell meters calibrated in mmol/L. Understanding conversions helps you interpret readings correctly.
Reading International Research
Medical studies from Europe, Australia, or Canada report values in mmol/L. Converting these values helps you compare findings with US-based research.
Using Imported Medical Devices
Some glucose meters or lab equipment purchased online use different unit systems. This converter ensures accurate interpretation regardless of device origin.
Communicating with Healthcare Providers
When consulting with international specialists or using telemedicine services across borders, unit conversion facilitates clear communication.
Understanding Lab Reports
Some laboratories report both units, while others use only one. This converter helps when your preferred unit isn’t displayed.
11. Frequently Asked Questions
What is the easiest way to convert mg/dL to mmol/L for glucose?
For glucose specifically, divide your mg/dL value by 18. This quick calculation provides a close approximation. For example, 180 mg/dL divided by 18 equals 10 mmol/L. Our calculator above provides exact results using the precise molecular weight.
Why does my glucose meter show different units than my lab report?
Glucose meters and laboratories may use different unit standards. US-purchased meters typically display mg/dL, while meters from other countries show mmol/L. Both measurements are accurate when converted properly.
Is 7 mmol/L the same as 126 mg/dL?
Yes, these values are equivalent for blood glucose. A fasting glucose of 7.0 mmol/L (126 mg/dL) is the diagnostic threshold for diabetes according to international guidelines.
Can I use the same conversion factor for all substances?
No. Each substance has a unique molecular weight that determines its conversion factor. Glucose, cholesterol, and other substances all require different calculations. Always use the correct molecular weight for accurate conversions.
What is the difference between mmol/L and µmol/L?
These units differ by a factor of 1,000. One mmol/L equals 1,000 µmol/L. Substances measured in very small concentrations, like creatinine and bilirubin, often use µmol/L for convenience.
How accurate is this calculator?
This calculator uses scientifically verified molecular weights and standard conversion formulas. Results are accurate to four decimal places. However, always verify critical medical decisions with your healthcare provider.
Why do some countries still use mg/dL?
The United States, Japan, and a few other nations established their medical systems before international standardization efforts. Changing measurement systems requires updating medical education, equipment, and documentation, which takes considerable time and resources.
Can I convert my A1C percentage to mmol/mol?
A1C (glycated hemoglobin) uses a different conversion formula than blood glucose. The conversion between percentage and mmol/mol requires a separate calculation not covered by this converter.
12. Final Thoughts
Converting mg/dL to mmol/L becomes simple once you understand the underlying formula. Our calculator eliminates manual calculations and provides instant, accurate results.
Remember that both units measure the same substances in your blood. The numbers change, but the underlying health information remains identical.
Always discuss your lab results with a qualified healthcare provider. Unit conversion tools help you understand your numbers, but proper medical interpretation requires professional expertise.
Bookmark this page for quick access whenever you need to convert medical lab values. Share it with others who may benefit from understanding international measurement differences.