Blood Sugar Calculator

Convert blood sugar between mg/dL and mmol/L, estimate HbA1c from average glucose and category.

Blood Sugar Calculator

Convert blood sugar between mg/dL and mmol/L, estimate HbA1c from average glucose and category.

Glucose value

Unit

Average glucose (mg/dL) for HbA1c

Enter values above and click Calculate — results will appear here with the formula explained.

mmol = mg/dL /18.01559; HbA1c% = (avg +46.7)/28.7 (ADAG)

How does this work?

Convert via 18.01559. HbA1c estimates 3-month average: ADAG formula (avg+46.7)/28.7 gives %. Categories: <5.7 normal, 5.7-6.4 prediabetes, ≥6.5 diabetes (diagnosis needs lab).

This is screening, not diagnosis. Home meters vary ±15%. For YMYL diabetes, confirm with lab HbA1c and clinician.

Fasting 100-125 mg/dL is prediabetes range, ≥126 diabetes (repeated).

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Disclaimer: Results are estimates for informational purposes only and do not constitute professional medical advice.

Quick Answer

Blood Sugar Calculator: Convert blood sugar between mg/dL and mmol/L, estimate HbA1c from average glucose and category. Formula: mmol = mg/dL /18. Example: With 126 mg/dL =7.

How to Use This Calculator

1Enter glucose value and unit to convert, plus average glucose for HbA1c estimate.
2Calculate to see mmol/L or mg/dL, HbA1c % and category.
3Track fasting vs post-meal separately.

Formula Used

mmol = mg/dL /18.01559; HbA1c% = (avg +46.7)/28.7 (ADAG)

Convert via 18.01559. HbA1c estimates 3-month average: ADAG formula (avg+46.7)/28.7 gives %. Categories: <5.7 normal, 5.7-6.4 prediabetes, ≥6.5 diabetes (diagnosis needs lab).

This is screening, not diagnosis. Home meters vary ±15%. For YMYL diabetes, confirm with lab HbA1c and clinician.

Fasting 100-125 mg/dL is prediabetes range, ≥126 diabetes (repeated).

AdSense ready — add NEXT_PUBLIC_GOOGLE_ADSENSE_PUBLISHER_ID

728×90 — AdSense

Worked Example

With 126 mg/dL =7.0 mmol/L. Average 154 mg/dL gives HbA1c ~7.0%, diabetes threshold.

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Frequently Asked Questions

QWhat is HbA1c?

3-month average glucose. <5.7% normal, 5.7-6.4 prediabetes, ≥6.5 diabetes.

QAccurate?

ADAG estimate ±0.5%. Lab HbA1c is definitive.

QFasting vs random?

Fasting ≥126 or random ≥200 with symptoms suggests diabetes — lab confirm.

Formula Used

mmol = mg/dL /18.01559; HbA1c% = (avg +46.7)/28.7 (ADAG)

Convert via 18.01559. HbA1c estimates 3-month average: ADAG formula (avg+46.7)/28.7 gives %. Categories: <5.7 normal, 5.7-6.4 prediabetes, ≥6.5 diabetes (diagnosis needs lab).

This is screening, not diagnosis. Home meters vary ±15%. For YMYL diabetes, confirm with lab HbA1c and clinician.

Fasting 100-125 mg/dL is prediabetes range, ≥126 diabetes (repeated).