🩸 Blood Sugar Converter

Convert between blood sugar units for health, medicine, and diabetes management.

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Ranges
Diagnosis
Reference
FAQ

Blood Sugar Converter

Enter a value in either mg/dL or mmol/L. The other field will update automatically.

Target Ranges

TimingNormalPrediabetesDiabetes
Fasting70-99 mg/dL
3.9-5.5 mmol/L		100-125 mg/dL
5.6-6.9 mmol/L		≥126 mg/dL
≥7.0 mmol/L
2h After Meal<140 mg/dL
<7.8 mmol/L		140-199 mg/dL
7.8-11.0 mmol/L		≥200 mg/dL
≥11.1 mmol/L
Random<200 mg/dL
<11.1 mmol/L		-≥200 mg/dL
≥11.1 mmol/L

Diagnosis Criteria

Diabetes is diagnosed if any of the following are met:
  • Fasting glucose ≥126 mg/dL (≥7.0 mmol/L)
  • 2h after meal ≥200 mg/dL (≥11.1 mmol/L)
  • Random glucose ≥200 mg/dL (≥11.1 mmol/L) with symptoms
  • HbA1c ≥6.5%
Prediabetes: Fasting 100-125 mg/dL (5.6-6.9 mmol/L), 2h after meal 140-199 mg/dL (7.8-11.0 mmol/L), HbA1c 5.7-6.4%.

Reference & Formula

ConversionFormula
mg/dL → mmol/Lmmol/L = mg/dL ÷ 18
mmol/L → mg/dLmg/dL = mmol/L × 18
References: ADA, WHO, "Diabetes Care" guidelines, MedlinePlus

Frequently Asked Questions

  • What is a normal blood sugar? Fasting: 70-99 mg/dL (3.9-5.5 mmol/L)
  • How do I convert mg/dL to mmol/L? Divide by 18.
  • How do I convert mmol/L to mg/dL? Multiply by 18.
  • What is prediabetes? Blood sugar higher than normal but not diabetes.
  • What is HbA1c? A long-term average of blood sugar (3 months).