- βEasy-to-read reference chart for all blood sugar categories
- βCovers fasting, post-meal, and A1C readings in one place
- βIncludes actionable steps for both high and low blood sugar
Why Your Blood Sugar Numbers Matter
If you live with diabetes or prediabetes, your blood sugar readings are more than just numbers on a screen β they tell the story of how your body is managing glucose throughout the day. Knowing what each number means can help you make smarter decisions about food, activity, medication, and lifestyle habits.
The Blood Sugar Chart at a Glance
Blood sugar levels are measured in milligrams per deciliter (mg/dL) in the United States. Here is a general reference chart used by most healthcare providers:
| Category | Fasting (mg/dL) | 2 Hours After Eating (mg/dL) |
|---|---|---|
| Normal | 70 β 99 | Less than 140 |
| Prediabetes | 100 β 125 | 140 β 199 |
| Diabetes | 126 or higher | 200 or higher |
| Low (Hypoglycemia) | Below 70 | Below 70 |
Understanding Fasting Blood Sugar
A fasting blood sugar test is taken after at least 8 hours without eating or drinking anything other than water. This reading gives your doctor a baseline look at how your body regulates glucose overnight without the influence of food.
- 70β99 mg/dL: Normal range. Your body is managing glucose efficiently.
- 100β125 mg/dL: Prediabetes territory. Lifestyle changes can still reverse this trend.
- 126 mg/dL or above: On two separate tests, this confirms a diabetes diagnosis.
Postprandial (After-Meal) Blood Sugar
Postprandial readings are taken two hours after the first bite of a meal. These numbers reveal how well your body processes carbohydrates and glucose from food.
- Under 140 mg/dL: Normal and healthy response.
- 140β199 mg/dL: Impaired glucose tolerance, a sign of prediabetes.
- 200 mg/dL or above: Indicates diabetes and may require immediate medical attention.
What Is Low Blood Sugar (Hypoglycemia)?
Hypoglycemia occurs when blood sugar drops below 70 mg/dL. Common symptoms include shakiness, sweating, confusion, and dizziness. Severe hypoglycemia (below 54 mg/dL) is a medical emergency. If you experience a low, treat it immediately with 15 grams of fast-acting carbohydrates β like glucose tablets or 4 ounces of juice β and recheck after 15 minutes.
A1C: The Big-Picture Number
Beyond daily readings, your A1C test reflects your average blood sugar over the past 2β3 months. An A1C below 5.7% is normal, 5.7β6.4% signals prediabetes, and 6.5% or higher indicates diabetes. Most people with diabetes aim to keep their A1C below 7%, though your personal target should be set with your doctor.
Choosing the Right Blood Glucose Meter
Accurate readings start with a quality glucose meter. Resources like mdsdiabetes.com offer expert guidance on selecting the right blood glucose meters, understanding your readings, and finding tools that fit your lifestyle and budget.
When to Contact Your Doctor
Reach out to your healthcare provider if you notice consistently high readings above 250 mg/dL, frequent lows below 70 mg/dL, or unexplained fluctuations. Never adjust medications without professional guidance.
Final Thoughts
Your blood sugar chart is one of the most powerful tools in your diabetes management toolkit. By understanding what every number means β from fasting levels to post-meal spikes β you can take confident, informed action every single day. Track consistently, act quickly on extremes, and always work closely with your healthcare team.