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Blood Sugar Converter — mg/dL and mmol/L
Convert your blood sugar value between mg/dL and mmol/L and instantly classify it as Normal, Prediabetes, or Diabetes.
Reference Ranges
Fasting Blood Sugar
Normal
No elevated risk.
< 100 mg/dL
< 5.6 mmol/L
Prediabetes
Elevated risk. Lifestyle changes recommended.
100 – 125 mg/dL
5.6 – 6.9 mmol/L
Diabetes
Diabetes range. Consult a doctor.
≥ 126 mg/dL
≥ 7.0 mmol/L
Postprandial Blood Sugar (2h after meal)
Normal
< 140 mg/dL
< 7.8 mmol/L
Prediabetes
140 – 199 mg/dL
7.8 – 11.0 mmol/L
Diabetes
≥ 200 mg/dL
≥ 11.1 mmol/L
Values can vary depending on measurement time, time of day, and diet. Not a substitute for medical advice.
Frequently Asked Questions
Which blood-sugar units exist?+
mg/dL (US, Germany) and mmol/L (UK, Canada, international studies). Conversion: 1 mmol/L = 18.016 mg/dL.
What are normal fasting values?+
Normal: < 100 mg/dL (5.6 mmol/L). Prediabetes: 100–125 mg/dL (5.6–6.9 mmol/L). Diabetes: ≥ 126 mg/dL (7.0 mmol/L). Source: ADA.
What are normal post-meal values?+
2 hours after eating: < 140 mg/dL (7.8 mmol/L) normal. 140–199 mg/dL (7.8–11.0 mmol/L) prediabetic. ≥ 200 mg/dL (11.1 mmol/L) diabetic.
What is hypoglycemia?+
Blood sugar < 70 mg/dL (3.9 mmol/L). Symptoms: shakiness, sweating, hunger, confusion. Values < 54 mg/dL (3.0 mmol/L) signify clinically significant hypoglycemia.
How often should I check?+
Type-1 diabetes: multiple times daily. Type-2 on insulin: 1–4×/day, on oral therapy as advised. Healthy people generally do not need self-monitoring.
Which factors influence blood sugar?+
Diet (carbs), exercise, stress, sleep, illness, medication, hormones. Time of day (dawn phenomenon) and alcohol also matter.
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Blood Sugar Converter — mg/dL to mmol/L Guide
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