BloodGlucoseValueUnderstand every reading

Blood Glucose 328 mg/dL tested - is it bad?

Blood glucose meter showing 328 mg/dL
  • Without diabetes, fastingDiabetes range
  • Without diabetes, 2 h after eatingDiabetes range
  • With diabetes, before a mealVery high
  • With diabetes, after a mealVery high
  • In mmol/L18.2 mmol/L

Get medical advice now

  • Check ketones if you use insulin. Moderate or high ketones, vomiting, abdominal pain, deep fast breathing or fruity-smelling breath can mean diabetic ketoacidosis — call 911 (US) or your local emergency number or go to the emergency room.
  • Very high readings (especially above 600 mg/dL, often shown as "HI") with extreme thirst, confusion or drowsiness can mean hyperosmolar hyperglycemic state — an emergency.
  • With diabetes and none of these signs: contact your care team today and re-check every 2–3 hours.
  • Without known diabetes: see a doctor today.

If you don't have diabetes

328 mg/dL is in the diabetes range whether fasting or after a meal. A random reading of 200 mg/dL or more together with typical symptoms (thirst, frequent urination, weight loss) is enough for a diagnosis — see a doctor today.

Fasting (8+ hours without food)

Diabetes rangeScale with 328 mg/dL marked5570100126328 mg/dL

2 hours after eating (or glucose tolerance test)

Diabetes rangeScale with 328 mg/dL marked5570140200328 mg/dL

If you have diabetes

328 mg/dL is very high. Check ketones if you use insulin and contact your care team today. With moderate or high ketones, vomiting, abdominal pain, deep fast breathing, extreme thirst, confusion or drowsiness, call 911 (US) or your local emergency number (see the box above).

Before a meal / fasting

Very highScale with 328 mg/dL marked547080>130>180>240300328 mg/dL

1–2 hours after a meal

Very highScale with 328 mg/dL marked5470180>240300328 mg/dL

Targets for most non-pregnant adults (American Diabetes Association (ADA) Standards of Care). Your own targets may be different — for example in pregnancy, for children, older adults or people prone to lows. See pregnancy targets.

328 mg/dL as an average: HbA1c 13.1%

If 328 mg/dL were your average glucose over two to three months, it would match an HbA1c of about 13.1% (above the common treatment goal of below 7%). A single reading says little about your HbA1c — it is the long-term average that counts. Learn more in how to measure blood sugar.

Make sure the number is right

  • Wash and dry your hands before a finger-stick: fruit juice or sugar on the skin can raise the result a lot.
  • Home meters may differ from a lab value by up to about 15%. At 328 mg/dL that means roughly 279–377 mg/dL.
  • CGM sensors measure tissue fluid and lag 5–15 minutes behind blood when glucose changes quickly — confirm lows with a finger-stick.

Check another reading

Nearby values

Sources: ADA Standards of Care · ADA: Hyperglycemia · MedlinePlus: Diabetic ketoacidosis · ADAG study (HbA1c and average glucose) · MedlinePlus: Blood glucose test

This page explains one reading in general terms. It is not a diagnosis or a treatment instruction. Follow the plan agreed with your doctor or diabetes team.