For most adults with diabetes, a good blood sugar level is 80 to 130 mg/dL before meals and below 180 mg/dL one to two hours after eating. These are the targets recommended by the American Diabetes Association, but your ideal range can shift depending on your age, whether you’re pregnant, and how long you’ve had diabetes.
Target Ranges for Most Adults
The standard daily targets for nonpregnant adults with diabetes break down into two key windows:
- Before meals (fasting): 80 to 130 mg/dL (4.4 to 7.2 mmol/L)
- 1 to 2 hours after eating: below 180 mg/dL (10.0 mmol/L)
These numbers apply whether you have Type 1 or Type 2 diabetes. They represent the sweet spot where your blood sugar is high enough to fuel your body but low enough to avoid the damage that persistent high glucose causes to blood vessels, nerves, and organs over time.
What Your A1C Should Be
While daily finger sticks or a continuous glucose monitor give you a snapshot, your A1C reflects your average blood sugar over the past two to three months. The goal for most adults with diabetes is an A1C below 7%, which corresponds to an estimated average glucose of roughly 154 mg/dL.
That said, A1C targets are not one-size-fits-all. Younger adults who were recently diagnosed and have no major complications can sometimes aim lower, closer to 6.5%. Older adults or people who are prone to dangerous lows may do better with a slightly higher ceiling. What matters is finding a target that keeps you safe from both high and low blood sugar.
Targets for Older Adults
For older adults managing multiple health conditions, the priority shifts toward avoiding low blood sugar, which can cause falls, confusion, and hospitalization. Diabetes Canada’s guidelines lay out adjusted targets based on functional status:
- Functionally dependent older adults: A1C of 7.1 to 8.0%, with before-meal readings of roughly 90 to 144 mg/dL
- Frail adults or those with dementia: A1C of 7.1 to 8.5%, with before-meal readings of roughly 108 to 162 mg/dL
- End of life: A1C testing is not recommended. The focus is on comfort, avoiding symptoms from extremely high glucose and preventing any lows.
These relaxed targets reflect the reality that tight glucose control carries risks when someone is more vulnerable to the effects of hypoglycemia. A slightly higher average is safer than frequent dangerous drops.
Targets During Pregnancy
Pregnancy demands tighter control because even moderately elevated blood sugar can affect fetal development. The American College of Obstetricians and Gynecologists recommends these goals for pregnant women with diabetes:
- Fasting: below 95 mg/dL
- 1 hour after eating: below 140 mg/dL
- 2 hours after eating: below 120 mg/dL
These apply to both pre-existing diabetes and gestational diabetes. The fasting target in particular is noticeably lower than the standard adult range, which is why pregnancy often requires more frequent monitoring and medication adjustments.
Targets for Children and Teens
The International Society for Pediatric and Adolescent Diabetes recommends an A1C at or below 7% for most children with diabetes, with a more ambitious target of 6.5% or lower for kids using advanced technology like insulin pumps and continuous glucose monitors, as long as that tighter goal doesn’t create undue stress or too many lows.
For daily readings, the targets are 70 to 144 mg/dL before meals and 70 to 180 mg/dL after meals. These are slightly wider windows than adult targets, reflecting the unpredictability of children’s eating patterns and activity levels.
Understanding Time in Range
If you use a continuous glucose monitor, you’ll encounter a metric called “time in range.” This measures the percentage of your day spent between 70 and 180 mg/dL. The goal for most people is at least 70% of readings in that range, which works out to roughly 17 out of 24 hours.
Time in range is useful because it captures something A1C misses: variability. Two people can have the same A1C, but one might have steady glucose all day while the other swings between dangerous highs and lows. A high time in range generally means fewer spikes and fewer crashes, which translates to feeling better day to day and fewer long-term complications.
Alongside spending 70% or more in range, the targets also include spending less than 4% of the day below 70 mg/dL and less than 1% below 54 mg/dL. Those low-end thresholds matter because hypoglycemia can be immediately dangerous in a way that a brief high reading is not.
When Blood Sugar Drops Too Low
Knowing what’s “too low” is just as important as knowing your target. Low blood sugar, or hypoglycemia, is classified in three levels:
- Level 1: 54 to 69 mg/dL. You might feel shaky, sweaty, or irritable. This usually responds to a quick-acting carbohydrate like juice or glucose tablets.
- Level 2: below 54 mg/dL. This is clinically significant and needs immediate treatment. Confusion and difficulty concentrating become more likely.
- Level 3: a severe event where you need someone else’s help to recover, regardless of the number on your meter. This can involve loss of consciousness or seizures.
If you’re hitting Level 1 lows frequently, your targets or medication may need adjusting. Occasional mild lows happen, but they shouldn’t be a regular part of your week.
Why Morning Readings Run High
Many people with diabetes notice their fasting blood sugar is higher than expected, even when they ate well the night before. Two phenomena explain this. The more common one is the dawn phenomenon: between roughly 3 a.m. and 8 a.m., your body releases hormones like cortisol and growth hormone that signal the liver to produce more glucose. This is a normal wake-up mechanism, but without enough insulin to handle the surge, your morning reading climbs.
The less common cause is the Somogyi effect, where blood sugar drops too low overnight and your body overcorrects by flooding the bloodstream with glucose. The result looks the same on your morning meter, but the underlying problem is different. Checking your glucose around 2 or 3 a.m. for a few nights, or reviewing overnight data from a continuous monitor, can help distinguish between the two. If you’re low at 3 a.m. and high at 7 a.m., the Somogyi effect is likely. If you’re normal or slightly elevated at 3 a.m. and higher by morning, the dawn phenomenon is the culprit.
How Often to Check
Testing frequency depends on your treatment. If you have Type 1 diabetes, expect to check 4 to 10 times per day or use a continuous glucose monitor. For Type 2 diabetes managed with insulin, testing several times daily is typical, often before meals and at bedtime. If you manage Type 2 with non-insulin medications, diet, and exercise, daily testing may not be necessary, though periodic checks help you understand how specific foods and activities affect your levels.
Converting Between Units
Blood sugar is measured in mg/dL in the United States and mmol/L in most other countries. To convert, multiply mg/dL by 0.0555. A few common reference points:
- 70 mg/dL = 3.9 mmol/L (lower boundary of normal)
- 100 mg/dL = 5.6 mmol/L (upper end of a normal fasting level for someone without diabetes)
- 130 mg/dL = 7.2 mmol/L (upper pre-meal target for most adults with diabetes)
- 180 mg/dL = 10.0 mmol/L (post-meal target ceiling)