Basically, the normal blood sugar reading should be as following (according to ADA - American Diabetes Association for adult): Blood glucose before meal: 70 – 130 mg/dl. Blood glucose 2 hours after meal: <180 mg/dl. A1C ( which shows how well you’ve been managing diabetes during the last 3 months: <7.0%.These are the normal figures that you should get most of the times when you perform a blood glucose test.