Glucose (Fasting)
Fasting glucose is a measure of blood glucose levels after an overnight fast (usually at least 8 hours). A fasting blood sugar of less than 100 mg/dL is normal. A fasting blood sugar of 100 to 125 mg/dL is considered prediabetes. A value of 126 mg/dL or higher on two separate occasions is diagnostic for diabetes.
Resources: Mayo Clinic - Diabetes