A blood sugar test result is only useful if you know what the numbers mean. This is where a blood sugar level chart becomes helpful.
Whether you have Type 1 Diabetes, Type 2 Diabetes, Prediabetes, or are simply monitoring your health, understanding blood sugar ranges can help you identify whether your glucose levels are within a healthy range.
Many people check their blood sugar at home but are unsure if their results are normal, too high, or too low. A blood sugar chart provides a quick reference that makes those readings easier to understand.
In this guide, we'll focus on blood sugar level charts, target ranges, and how to interpret your results correctly.
What Is a Blood Sugar Level Chart?
A blood sugar level chart is a reference table that shows glucose ranges for different situations.
These charts help people understand:
- Normal blood sugar levels
- Prediabetes ranges
- Diabetes ranges
- Target blood sugar goals
- Low blood sugar levels
- High blood sugar levels
Doctors often use these charts to evaluate diabetes management and overall glucose control.
Blood Sugar Level Chart for Adults
The following chart shows common blood sugar ranges for adults.
Blood Sugar Level Chart (mg/dL)
| Blood Sugar Status | Fasting (Before Eating) | 2 Hours After Eating |
| Normal | 70–99 | Less than 140 |
| Prediabetes | 100–125 | 140–199 |
| Diabetes | 126 or higher | 200 or higher |
These values are commonly used to help diagnose and monitor diabetes.
Target Blood Sugar Chart for People With Diabetes
People who already have diabetes often follow target ranges recommended by their healthcare provider.
General Diabetes Blood Sugar Targets
| Time of Testing | Target Range (mg/dL) |
| Before Meals | 80–130 |
| 1–2 Hours After Meals | Less than 180 |
| Bedtime | Individual target set by doctor |
Target ranges may vary depending on age, pregnancy status, medications, and overall health.
Fasting Blood Sugar Level Chart
A fasting blood sugar test measures glucose levels after not eating for at least 8 hours.
Fasting Blood Sugar Chart
| Fasting Blood Sugar (mg/dL) | Meaning |
| Below 70 | Low Blood Sugar |
| 70–99 | Normal |
| 100–125 | Prediabetes |
| 126 or Higher | Diabetes Range |
Fasting blood sugar is one of the most commonly used diabetes screening tests.
Blood Sugar Chart After Eating
Blood sugar naturally rises after meals.
The amount of increase depends on:
- Food choices
- Portion size
- Physical activity
- Diabetes medications
- Insulin production
Blood Sugar Chart 2 Hours After Eating
| Blood Sugar Reading (mg/dL) | Meaning |
| Less than 140 | Normal |
| 140–199 | Prediabetes Range |
| 200 or Higher | Diabetes Range |
Consistently high after-meal readings may indicate poor glucose control.
Low Blood Sugar Chart
Low blood sugar, also called hypoglycemia, can occur in people who use insulin or certain diabetes medications.
Low Blood Sugar Levels
| Blood Sugar Level (mg/dL) | Category |
| 70 or Below | Low Blood Sugar |
| Below 54 | Significant Low Blood Sugar |
| Below 40 | Medical Emergency |
Low blood sugar requires prompt attention because symptoms can worsen quickly.
High Blood Sugar Chart
High blood sugar, also known as hyperglycemia, occurs when glucose levels remain above the target range.
High Blood Sugar Levels
| Blood Sugar Level (mg/dL) | Category |
| 180+ After Meals | Higher Than Target |
| 200+ | High Blood Sugar |
| 250+ | Very High Blood Sugar |
| 300+ | Medical Attention May Be Needed |
Persistent high readings should be discussed with a healthcare provider.
A1C Chart and Average Blood Sugar Levels
The A1C test provides information about average blood sugar levels over the previous 2 to 3 months.
A1C Chart
| A1C (%) | Category |
| Below 5.7% | Normal |
| 5.7%–6.4% | Prediabetes |
| 6.5% or Higher | Diabetes |
Estimated Average Blood Sugar From A1C
| A1C (%) | Estimated Average Glucose (mg/dL) |
| 5 | 97 |
| 6 | 126 |
| 7 | 154 |
| 8 | 183 |
| 9 | 212 |
| 10 | 240 |
The A1C test helps show long-term blood sugar control rather than a single reading.
Blood Sugar Level Chart by Time of Day
Blood sugar levels naturally change throughout the day.
Typical Daily Blood Sugar Targets
| Time | Target Blood Sugar |
| Before Breakfast | 80–130 mg/dL |
| Before Lunch | 80–130 mg/dL |
| Before Dinner | 80–130 mg/dL |
| 1–2 Hours After Meals | Less than 180 mg/dL |
| Bedtime | Individual Goal |
Tracking readings at different times can help identify patterns.
Why Blood Sugar Levels Change
Many factors can affect your glucose readings.
Food Choices
Carbohydrates have the biggest impact on blood sugar levels.
Exercise
Physical activity usually helps lower blood sugar.
Stress
Stress hormones can cause blood sugar levels to rise.
Illness
Being sick may increase glucose levels even if you are eating normally.
Diabetes Medication
Insulin and diabetes medicines can significantly affect readings.
Understanding these factors makes blood sugar charts more useful.
How to Use a Blood Sugar Level Chart
A chart is most helpful when combined with regular testing.
Try these steps:
- Test your blood sugar consistently.
- Record the results.
- Compare readings with the chart.
- Look for patterns over time.
- Share your results with your healthcare provider.
Tracking trends is often more valuable than focusing on a single reading.
When Should You Be Concerned About Your Blood Sugar Numbers?
Occasional fluctuations are common.
However, you should seek medical advice if:
- Blood sugar remains consistently above target.
- You experience frequent low blood sugar episodes.
- Readings suddenly change without explanation.
- Blood sugar exceeds your healthcare provider's recommended range.
Early intervention can help prevent complications.
Quick Reference Blood Sugar Level Chart
| Category | Blood Sugar Level |
| Low Blood Sugar | Below 70 mg/dL |
| Normal Fasting | 70–99 mg/dL |
| Prediabetes Fasting | 100–125 mg/dL |
| Diabetes Fasting | 126+ mg/dL |
| Target Before Meals (Diabetes) | 80–130 mg/dL |
| Target After Meals (Diabetes) | Less than 180 mg/dL |
This chart provides a simple overview of commonly used blood sugar ranges.
Final Thoughts
A blood sugar level chart helps turn glucose readings into meaningful information. Instead of simply seeing a number on a meter, you can understand whether your blood sugar is within a healthy range, slightly elevated, or potentially concerning.
Regular monitoring, combined with a clear understanding of blood sugar charts, can help you make informed decisions about food, exercise, medications, and diabetes management. While charts provide useful guidance, your healthcare provider may recommend personalized target ranges based on your individual health needs.
References
- American Diabetes Association (ADA)
- Centers for Disease Control and Prevention (CDC)
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
- National Health Service (NHS)
Related Diabetes Resources
- Smart devices for blood sugar monitoring
- Fasting blood sugar vs HbA1c for diabetes monitoring
- How sleep affects blood sugar levels
Medical Disclaimer
This article is for educational purposes only and should not be considered medical advice. Always consult your healthcare provider for personalized blood sugar targets and treatment recommendations.