How is pre-diabetes diagnosed?

A fasting blood sugar test is performed after you have had nothing by mouth (eating or drinking) for 10-12 hours. Normal fasting blood sugar is between 70 and 99 mg/dl for people who do not have diabetes. A normal random blood sugar result is between 70 and 140. The diagnosis of pre-diabetes is made when two blood tests show that your fasting blood sugar level is between 100 and 125 mg/dl, or if two random (anytime) blood sugar tests are greater than or equal to 140, but below 200.

Fasting Glucose Test

  • Normal: Less than 100
  • Pre-Diabetes: 100-125
  • Diabetes: 126 or higher

Random (Anytime) Glucose Test

  • Normal: Less than 140
  • Pre-Diabetes: 140-199
  • Diabetes: Greater than 200


  • Normal: Less than 5.7%
  • Pre-Diabetes: 5.7-6.4%
  • Diabetes: Greater than 6.5%

Source: American Diabetes Association 2013

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