Blood Sugar Converter & HbA1c Calculator

Q: How do I convert blood sugar from mg/dL to mmol/L?

To convert blood glucose from mg/dL to mmol/L, divide the mg/dL value by 18.0182 (or multiply by 0.0555). For example, 180 mg/dL ÷ 18.0182 = 10.0 mmol/L.

Q: How do I convert blood sugar from mmol/L to mg/dL?

To convert blood glucose from mmol/L to mg/dL, multiply the mmol/L value by 18.0182. For example, 7.0 mmol/L × 18.0182 = 126 mg/dL.

Q: Which countries use mg/dL vs mmol/L for glucose measurement?

The United States, France, Japan, Israel, Italy, Germany, and parts of Latin America use mg/dL (milligrams per deciliter). The United Kingdom, Canada, Australia, New Zealand, China, and most European countries follow the WHO standard of mmol/L (millimoles per liter).

Q: How is HbA1c converted to Estimated Average Glucose (eAG)?

The American Diabetes Association uses the ADAG formula: eAG (mg/dL) = 28.7 × HbA1c (%) - 46.7, or eAG (mmol/L) = 1.59 × HbA1c (%) - 2.59. An HbA1c of 7.0% corresponds to an average glucose of 154 mg/dL (8.6 mmol/L).

Q: What is a normal fasting blood sugar level?

According to ADA guidelines, a normal fasting blood glucose level is between 70 and 99 mg/dL (3.9 to 5.5 mmol/L). Fasting levels of 100 to 125 mg/dL indicate pre-diabetes, and 126 mg/dL or higher on two separate tests indicates diabetes.

Q: What are normal post-meal (postprandial) glucose targets?

For adults without diabetes, normal blood sugar 2 hours after a meal is under 140 mg/dL (7.8 mmol/L). For diabetic individuals, the ADA recommended target is under 180 mg/dL (10.0 mmol/L).

Q: What is the difference between DCCT (%) and IFCC (mmol/mol) HbA1c units?

DCCT reports HbA1c as a percentage (e.g. 6.5%), widely used in the US. IFCC reports in mmol/mol (e.g. 48 mmol/mol), standard in the UK and Europe. The conversion formula is: IFCC = (DCCT - 2.15) × 10.929.

Q: What glucose level is considered hypoglycemia (low blood sugar)?

A blood glucose reading below 70 mg/dL (3.9 mmol/L) is clinically defined as hypoglycemia and requires immediate fast-acting carbohydrate intake (15g rule). Readings below 54 mg/dL (3.0 mmol/L) indicate severe hypoglycemia.

Convert blood glucose readings between mg/dL and mmol/L instantly, calculate 3-month HbA1c (eAG), and view real-time clinical target ranges.

Quick Presets:

Testing Condition: Adjusts clinical target ranges

US & Japan mg/dL

mg/dL

International (WHO) mmol/L

mmol/L

HbA1c (eAG) 31 mmol/mol

Normal Fasting Blood Glucose

Optimal

Low (<70) Normal (70–99) Pre-Diabetes (100–125) Diabetes (≥126)

Your reading is in the healthy fasting glucose range (70–99 mg/dL or 3.9–5.5 mmol/L).

90 mg/dL = 5.0 mmol/L (HbA1c ~ 4.8%)

Clinical Category	Fasting (mg/dL)	Fasting (mmol/L)	HbA1c (%)	HbA1c (mmol/mol)
Hypoglycemia (Low)	< 70	< 3.9	< 4.0%	< 20
Normal (Optimal)	70 – 99	3.9 – 5.5	4.0% – 5.6%	20 – 38
Pre-Diabetes (Impaired)	100 – 125	5.6 – 6.9	5.7% – 6.4%	39 – 46
Diabetes Range	≥ 126	≥ 7.0	≥ 6.5%	≥ 48

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Blood Sugar & Glucose Measurement 101

Blood glucose monitoring is essential for managing diabetes, identifying insulin resistance, and evaluating metabolic health. However, because different countries and glucometers report readings in either mg/dL (milligrams per deciliter) or mmol/L (millimoles per liter), patients and healthcare providers often need to convert between these standards.

Furthermore, converting daily blood glucose fingerstick measurements into an Estimated Average Glucose (eAG) helps patients predict their upcoming 3-month laboratory HbA1c test results.

mg/dL vs. mmol/L: Regional Standards

mg/dL measures glucose mass per deciliter of blood, standard in the United States, Japan, France, and Germany. mmol/L measures molecular molar concentration per liter, recommended by the World Health Organization (WHO) and standard across the UK, Canada, Australia, and China. The mathematical conversion factor is exactly 18.0182.

The Science of HbA1c Glycation

Hemoglobin A1c (HbA1c) measures the percentage of hemoglobin proteins in red blood cells that are coated with glucose. Because red blood cells live for approximately 120 days, HbA1c provides a weighted 3-month average of blood sugar levels unaffected by short-term daily dietary spikes.

The ADAG eAG Formula

The American Diabetes Association A1c-Derived Average Glucose study established the linear formula: eAG (mg/dL) = 28.7 × HbA1c - 46.7. This enables patients with continuous glucose monitors (CGMs) to project their clinical HbA1c laboratory score accurately.

ADA Target Thresholds

Normal fasting glucose is 70–99 mg/dL (3.9–5.5 mmol/L). Fasting readings of 100–125 mg/dL indicate pre-diabetes, and ≥126 mg/dL on multiple tests confirms diabetes. Postprandial (2-hour post-meal) targets are <140 mg/dL for non-diabetic adults and <180 mg/dL for diabetic patients.

Discover What You Can Calculate Today!

Instantly convert continuous glucose monitor (CGM) readings, translate European lab reports for US doctors, and estimate your 3-month HbA1c trajectory before your next clinic appointment.

Frequently Asked Questions