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Blood Sugar Conversion Calculator

Instantly convert blood glucose readings between mg/dL and mmol/L.

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Glucose Value

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Enter values above and click Calculate to see your result.

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Our AI assistant provides general estimates and advice only. Please consult a qualified healthcare professional before making any health-related decisions.

Formula

Core Formula

\frac{\text{mg/dL}}{18} = \text{mmol/L}

How it works: Uses the molar mass of glucose (180 g/mol) to convert between mass concentration and molar concentration.

Worked Example

180 mg/dL -> 10.0 mmol/L.

Blood Sugar Converter - mg/dL to mmol/L Instantly

Blood glucose can be measured in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L). The conversion factor comes from the molecular weight of glucose (180.16 g/mol), which simplifies to dividing or multiplying by 18.

mg/dL to mmol/L: divide by 18.0182. mmol/L to mg/dL: multiply by 18.0182
Normal fasting glucose: 70 to 100 mg/dL (3.9 to 5.6 mmol/L)
Prediabetes fasting range: 100 to 125 mg/dL (5.6 to 6.9 mmol/L)
Diabetes threshold: 126 mg/dL (7.0 mmol/L) or higher on two tests
The USA, Germany, Japan, and Israel use mg/dL. The UK, Canada, and Australia use mmol/L

Always confirm which unit system your glucose meter and lab reports use before interpreting results.

You can also calculate changes using our HbA1c to eAG Calculator, Kidney Health and CKD Risk Calculator or Insulin Correction Dose Calculator.

Frequently Asked Questions

Which countries use mg/dL?

The USA, Germany, Japan, and Israel are primary users of mg/dL for blood glucose reporting.

Which countries use mmol/L?

The UK, Canada, Australia, and most of Europe use mmol/L as the standard glucose unit.

How is the conversion factor 18 derived?

Glucose has a molecular weight of about 180.16 g/mol. Since mg/dL measures mass concentration and mmol/L measures molar concentration, dividing by 18.0182 converts between the two systems.

What is a normal fasting blood sugar?

Normal fasting glucose is 70 to 100 mg/dL (3.9 to 5.6 mmol/L). Values of 100 to 125 mg/dL (5.6 to 6.9 mmol/L) suggest prediabetes, and 126 mg/dL (7.0 mmol/L) or higher indicates diabetes.

Does my glucose meter show mg/dL or mmol/L?

It depends on the region where the meter was sold. Check the display units or user manual. Some meters allow you to switch between units in settings.

Why do different countries use different units?

It is a historical convention. The USA adopted mass-based units (mg/dL), while many other countries adopted the SI molar unit (mmol/L) recommended by the International Federation of Clinical Chemistry.

How can I put this Blood Sugar Conversion Calculator on my blog or website?

Yes, the Blood Sugar Conversion Calculator is fully embeddable. Tap "Embed" above to configure appearance and copy the code. It is free to use, works on any platform (HTML, WordPress, CMS), and adjusts to any screen size automatically. Visit calculory.com/services/embed-calculators for the complete guide.

Medical Disclaimer

This calculator is provided for informational and educational purposes only. It is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making any decisions based on these results. Do not disregard or delay seeking medical advice because of information obtained from this tool.

AI Assistant

Ask about this calculator

I can help you understand the blood sugar conversion calculator formula, interpret your results, and answer follow-up questions.

Try asking

Our AI assistant provides general estimates and advice only. Please consult a qualified healthcare professional before making any health-related decisions.

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