Prediabetes is a condition where blood sugar levels are higher than normal but not high enough to be considered diabetes. The American Diabetes Association (ADA) defines prediabetes as a fasting glucose of 100–125 milligrams per deciliter and/or an A1C of 5.7% to 6.4% . The A1C test is a simple blood test that measures the average blood sugar levels over the past 2 to 3 months. A normal A1C level is below 5.7%, a level of 5.7% to 6.4% indicates prediabetes, and a level of 6.5% or more indicates diabetes. The A1C test is one of the commonly used tests to diagnose prediabetes and diabetes, and is also the main test to help manage diabetes.