Fasting Blood Sugar Ranges and Units
Normal, prediabetes and diabetes ranges in mg/dL and mmol/L.
Ranges
A normal fasting level is 70 to 99 mg/dL (3.9 to 5.5 mmol/L), prediabetes is 100 to 125 and diabetes is 126 mg/dL or more on two tests.
Converting units
Divide mg/dL by 18 to get mmol/L, or multiply mmol/L by 18. Countries use different units, so check before comparing.
Low blood sugar
Below 70 mg/dL is low and below 54 is serious. Treat with 15 g of fast-acting carbohydrate and recheck in 15 minutes.
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mg/dL95
mmol/L5.3
A fasting level of 70–99 mg/dL is normal.
Educational content only. This article does not replace advice from a qualified health professional. Medical disclaimer.