Normal Blood Sugar Levels Chart
The Normal Blood Sugar Levels Chart is a health reference tool covering normal blood sugar levels chart by age, blood sugar chart fasting, blood sugar levels after eating, diabetic blood sugar chart. Use the chart below to look up values instantly. Printable and downloadable versions are available on this page.
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Blood Sugar Levels Reference Chart
| Measurement Timing | Normal (mg/dL) | Prediabetes (mg/dL) | Diabetes (mg/dL) | mmol/L Conversion Note |
|---|---|---|---|---|
| Fasting (8 hours no food) | Below 100 | 100–125 | ≥ 126 | Multiply mg/dL by 0.0556 for mmol/L |
| 1 hour after eating | Below 140 | 140–199 | ≥ 200 | Same conversion |
| 2 hours after eating | Below 140 | 140–199 | ≥ 200 | Same conversion |
| Random reading with symptoms | Below 140 | 140–199 | ≥ 200 | Same conversion |
Source: American Diabetes Association Standards of Care 2024
Blood Glucose Response — Normal, Prediabetes, and Diabetes
How blood glucose changes after eating across the three health categories.
Source: American Diabetes Association reference ranges
Blood Sugar Chart by Age
Blood sugar targets differ for children, general adults, and frail older adults — the ADA sets different goals to balance glucose control against the risk of dangerous hypoglycaemia.
| Patient Group | Fasting Target (mg/dL) | Post-Meal Target (mg/dL) | Notes |
|---|---|---|---|
| Children and teens with Type 1 diabetes | 90–130 | 90–150 | Higher targets reduce hypoglycaemia risk in children. |
| Most adults without diabetes | Below 100 | Below 140 at 2 hours | Standard normal range. |
| Adults with diabetes | 80–130 | Below 180 | ADA management goal. |
| Older adults — healthy | 80–130 | Below 180 | Same as general adult goal. |
| Older adults — complex or frail | 100–150 | Below 200 | Relaxed to prevent dangerous low readings. |
Source: ADA Standards of Care 2024
Dangerous Blood Sugar Levels
| Condition | Blood Sugar Level | Symptoms | What to Do |
|---|---|---|---|
| Mild hypoglycaemia (low) | Below 70 mg/dL | Shaky, sweaty, dizzy, confused | Eat 15 g of fast-acting carbohydrates (glucose tablet, juice). Recheck in 15 minutes. |
| Severe hypoglycaemia | Below 54 mg/dL | Confusion, inability to self-treat, loss of consciousness | Glucagon injection or call 911. Do not give food or drink to an unconscious person. |
| Hyperglycaemia (high) | Above 180 mg/dL | Thirst, frequent urination, blurry vision | Contact doctor if persistent over several readings. |
| Hyperglycaemic emergency (DKA or HHS) | Above 300 mg/dL | Nausea, vomiting, fruity breath, extreme fatigue | Seek emergency medical care immediately. |
Source: American Diabetes Association — Hypoglycemia
How to Test Blood Sugar at Home
- Wash hands with soap and warm water before testing — food residue on fingers can skew the reading.
- Insert a fresh test strip into your glucometer and lance the side of your fingertip with the lancing device.
- Apply a small drop of blood to the test strip.
- Read the result on the glucometer display in mg/dL or mmol/L.
- Record the reading, the time of day, and whether it was fasting, pre-meal, or post-meal.
Continuous Glucose Monitors (CGMs) such as Dexcom G7 and Abbott FreeStyle Libre provide real-time readings every few minutes without finger sticks and are increasingly covered by insurance for people with diabetes.
Blood Sugar Level Checker
Enter your fasting or post-meal glucose reading to get an instant classification, safe zone, action level, and 24-hour pattern tracker.
Enter your reading below to get an instant classification and action guidance.
Frequently Asked Questions
What is a normal fasting blood sugar level?
Below 100 mg/dL is the normal fasting range. A reading of 100 to 125 indicates prediabetes and 126 or above on two separate tests indicates diabetes.
What blood sugar level is dangerous?
Below 70 mg/dL requires immediate treatment to prevent loss of consciousness. Above 300 mg/dL is a hyperglycaemic emergency and requires urgent medical attention.
What is normal blood sugar 2 hours after eating?
Below 140 mg/dL at 2 hours post-meal is normal for a person without diabetes.
What does a blood sugar reading of 150 mean?
A post-meal reading of 150 is within the acceptable range for people managing diabetes (target below 180). A fasting reading of 150 would indicate diabetes.
How does exercise affect blood sugar?
Aerobic exercise generally lowers blood sugar by helping muscle cells absorb glucose from the bloodstream without needing insulin. Intense exercise can temporarily raise blood sugar before it drops.
What foods raise blood sugar the fastest?
White bread, white rice, sugary drinks, candy, and other high-glycaemic foods raise blood sugar fastest. Protein, fat, and high-fibre foods cause a much slower rise. Lean protein sources like steak have minimal impact on blood sugar — see the steak temperature chart for safe cooking temperatures that preserve nutritional quality.
Is a reading of 200 mg/dL normal after eating?
A blood sugar of 200 mg/dL at 2 hours after a meal meets the diagnostic threshold for diabetes.
What is the difference between blood sugar and A1C?
A blood sugar reading reflects your glucose level at a single moment in time. A1C reflects the average blood sugar over the past 90 days by measuring how much glucose has attached to haemoglobin in red blood cells. See the A1C chart for a full conversion table and category reference. High blood sugar can also affect kidney function — the urine color chart can help you monitor hydration and spot unusual colour changes that may warrant a doctor visit. Uncontrolled diabetes can damage the retina — the eye chart guide covers Snellen visual acuity scores, what they mean, and how often diabetic patients should have their eyes examined. Digestive symptoms often accompany blood sugar dysregulation — the Bristol Stool Chart is a useful reference for understanding stool consistency and bowel transit changes linked to diet, and the stool color chart can help identify colour changes that may indicate digestive or liver-related concerns.