Why do different countries use mg/dL versus mmol/L for blood sugar?

The United States, France, Japan, and India primarily use mass concentration (mg/dL), while the UK, Canada, Australia, and most European nations use molar concentration (mmol/L). Both measure the exact same blood glucose level.

What are normal fasting blood sugar ranges?

According to the American Diabetes Association (ADA), normal fasting blood sugar is 70–99 mg/dL (3.9–5.5 mmol/L); prediabetes is 100–125 mg/dL (5.6–6.9 mmol/L); and diabetes is diagnosed at 126 mg/dL (7.0 mmol/L) or higher on two separate tests.

How accurate is the estimated HbA1c calculation from a single glucose reading?

A single fingerstick glucose reading reflects instantaneous blood sugar. Estimated HbA1c provides an approximate average equivalent, but clinical HbA1c measures 2-to-3-month glycated red blood cell averages and requires a laboratory blood test.

Is this tool a substitute for professional medical advice?

No. This converter is an educational utility. Always consult your endocrinologist or physician for diabetes diagnosis, medication adjustments, and personalized glycemic targets.

Health & Calculators

Blood Sugar & Glucose Unit Converter

Convert blood glucose readings between mg/dL (US) and mmol/L (International) with reference range context.

Medical Disclaimer: This tool is for informational purposes only and is not a substitute for professional medical advice. Blood glucose reference ranges are general guidelines — consult your healthcare provider for personalized target values.

mg/dL (US)

mmol/L (International)

5.55

Conversion factor: 1 mmol/L = 18.0182 mg/dL

Reference Ranges (General Guidelines)

Measurementmg/dLmmol/L

Fasting (Normal)70–993.9–5.5

Fasting (Prediabetes)100–1255.6–6.9

Fasting (Diabetes)≥126≥7.0

Post-meal 2h (Normal)<140<7.8

Post-meal 2h (Prediabetes)140–1997.8–11.0

Post-meal 2h (Diabetes)≥200≥11.1

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What is Blood Sugar & Glucose Unit Converter?

The Blood Sugar Converter translates blood glucose values between international standard units (milligrams per deciliter mg/dL and millimoles per liter mmol/L) with bidirectional conversion. It also estimates approximate Glycated Hemoglobin (HbA1c %) levels and provides American Diabetes Association (ADA) fasting glucose benchmarks.

Designed for accuracy, speed, and privacy, this tool runs entirely on your local device with zero network latency.

How to Use the Blood Sugar & Glucose Unit Converter

1
Select your input unit direction: "mg/dL to mmol/L" or "mmol/L to mg/dL".
2
Enter your current blood glucose reading from your glucometer or lab report.
3
Review the converted value in the alternative unit and the estimated equivalent HbA1c percentage.
4
Compare your reading against the ADA fasting and post-prandial glycemic target ranges.

Formula & Calculation Logic

Applies the molecular weight ratio of D-glucose (180.156 g/mol, yielding the clinical factor 18.0182) and the Nathan et al. ADAG (A1c-Derived Average Glucose) linear regression formula for estimated HbA1c mapping.

mmol/L = mg/dL / 18.0182 | mg/dL = mmol/L * 18.0182 | Estimated HbA1c (%) = (mg/dL + 46.7) / 28.7

Blood Sugar & Glucose Unit Converter Frequently Asked Questions

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