100% x 90

A1c Calculator

Convert between Hemoglobin A1c and Average Blood Sugar levels

A1c & Average Blood Sugar Converter

Conversion Direction

Enter HbA1c Value

HbA1c (%)

HbA1c (mmol/mol)

100% x 250

A1c Reference Ranges

✅

Normal

Below 5.7%

42 mmol/mol

⚠️

Prediabetes

5.7% - 6.4%

42-47 mmol/mol

🚨

Diabetes

6.5% or higher

48+ mmol/mol

Testing Guidelines

Normal Range

Test every 3 years

Prediabetes

Test every 6-12 months

Diabetes

Test every 3-6 months

A1c Quick Facts

✓

Reflects 2-3 months of blood sugar levels

✓

No fasting required for testing

✓

Gold standard for diabetes diagnosis

✓

Target under 7% for most adults with diabetes

Understanding Hemoglobin A1c

What is HbA1c?

Hemoglobin A1c (HbA1c) is a form of hemoglobin that has glucose permanently attached to it. Since red blood cells live approximately 120 days, the A1c test provides an average picture of blood sugar levels over the past 2-3 months. This makes it an invaluable tool for diagnosing and monitoring diabetes.

ADAG Study Formula

Average Glucose (mg/dL) = A1c (%) * 28.7 - 46.7

This formula was derived from the A1C-Derived Average Glucose (ADAG) study, which correlated A1c values with continuous glucose monitoring data from thousands of participants.

Clinical Significance

A1c under 5.7%

Normal glucose metabolism. Continue healthy lifestyle habits.

A1c 5.7-6.4%

Prediabetes. High risk of developing type 2 diabetes. Lifestyle intervention crucial.

A1c 6.5% or higher

Diabetes diagnosis criteria. Requires immediate medical evaluation and treatment.

Why A1c vs Daily Glucose?

•Shows long-term glucose control, not just single moments
•No fasting required, can be done any time of day
•Less affected by stress, illness, or recent meals
•Standardized globally for diabetes management

📈 Diabetes Management Targets

Under 7%

Most Adults

with diabetes

Under 6.5%

Healthy Adults

without complications

Under 8%

Older Adults

with complications

⚠️ Important Medical Disclaimer

• This calculator is for educational purposes only and should not replace professional medical advice

• A1c values may be affected by certain medical conditions, medications, or ethnic factors

• Diabetes diagnosis should always be confirmed by healthcare professionals using multiple tests

• Consult your healthcare provider for personalized diabetes management and target A1c goals