What Should Your Blood Sugar Be? Normal Ranges

A healthy blood sugar level for someone without diabetes is 70 to 99 mg/dL when fasting and under 140 mg/dL two hours after eating. These numbers shift depending on timing, age, pregnancy, and whether you’re managing diabetes, so knowing which number applies to your situation matters more than memorizing a single target.

Fasting Blood Sugar

Fasting blood sugar is measured after you haven’t eaten for at least eight hours, usually first thing in the morning. For a healthy adult without diabetes, the normal range is 70 to 99 mg/dL (3.9 to 5.5 mmol/L). Some people naturally run between 50 and 70 mg/dL without any symptoms or problems, and that can be perfectly normal too.

Once fasting glucose hits 100 to 125 mg/dL, it falls into the prediabetes range. A fasting reading of 126 mg/dL or higher, confirmed on a second test, meets the diagnostic threshold for type 2 diabetes. These cutoffs come from the American Diabetes Association and are the same ones your doctor uses when interpreting lab work.

After Meals

Blood sugar rises after you eat, and that’s completely normal. It typically peaks about one to two hours after your first bite, then gradually comes back down. For someone without diabetes, the two-hour mark should be below 140 mg/dL. If it consistently lands between 140 and 199, that signals impaired glucose tolerance, another marker of prediabetes.

The size and composition of your meal matters. A plate heavy in refined carbohydrates will push your blood sugar higher and faster than a balanced meal with protein, fat, and fiber. You don’t need to test after every meal unless your doctor has asked you to, but if you’re monitoring at home, the two-hour window is the standard checkpoint.

A1C: The Bigger Picture

While a finger stick captures a single moment, the A1C test reflects your average blood sugar over the previous two to three months. It measures the percentage of hemoglobin in your red blood cells that has glucose attached to it. A normal A1C is below 5.7%. Between 5.7% and 6.4% indicates prediabetes. An A1C of 6.5% or higher means diabetes.

If you already have diabetes, the general target is an A1C of 7% or less. Your doctor may set a slightly different goal depending on your age, how long you’ve had diabetes, and other health conditions. Older adults or people prone to dangerous lows sometimes aim for a somewhat higher A1C to reduce the risk of hypoglycemia.

Blood Sugar During Pregnancy

Pregnancy changes the targets. Whether you have gestational diabetes or entered pregnancy with an existing diagnosis, the recommended levels are tighter than the standard adult ranges. The American College of Obstetricians and Gynecologists recommends a fasting level below 95 mg/dL, below 140 mg/dL one hour after eating, and below 120 mg/dL at the two-hour mark.

These stricter targets exist because sustained high blood sugar during pregnancy increases the risk of complications for both mother and baby, including excessive birth weight and delivery complications. Most pregnant women are screened for gestational diabetes between 24 and 28 weeks.

Blood Sugar in Children

Normal ranges for young children differ slightly from adults. Infants typically run between 40 and 90 mg/dL. Children under two have a normal range of 60 to 100 mg/dL. After age two, the reference range aligns closely with adults. Children with type 1 diabetes have individualized targets that their care team sets based on age and risk of lows.

When Blood Sugar Drops Too Low

Blood sugar below 70 mg/dL is considered low, a condition called hypoglycemia. Early symptoms include shakiness, sweating, a fast heartbeat, dizziness, sudden hunger, and irritability or anxiety. These are your body’s warning signals that your brain needs more fuel.

A drop below 54 mg/dL is classified as severe. At that level, symptoms escalate to weakness, difficulty walking or seeing clearly, confusion, and in extreme cases, seizures or loss of consciousness. Hypoglycemia is most common in people taking insulin or certain diabetes medications, but it can occasionally happen in people without diabetes after prolonged fasting or intense exercise.

Why Morning Readings Run High

If you check your blood sugar first thing in the morning and find it higher than expected, you’re not alone. About half of people with type 1 or type 2 diabetes experience what’s called the dawn phenomenon. In the hours before you wake up, your body releases cortisol and growth hormone, which signal the liver to push out stored glucose. This gives you the energy to start your day. In a healthy pancreas, insulin rises to match. If you have diabetes, your body can’t compensate, so you wake up with an elevated reading.

A less common cause is the Somogyi effect, where blood sugar drops too low overnight and the body overcorrects by flooding the bloodstream with glucose. Waning insulin, particularly if a long-acting dose was taken too early or the dose is too low, can also be responsible. If your morning numbers are consistently off, tracking your blood sugar at bedtime and around 2 or 3 a.m. for a few nights can help pinpoint the pattern.

Continuous Monitor Targets

If you wear a continuous glucose monitor (CGM), you’ll encounter a metric called Time in Range, or TIR. This measures the percentage of the day your blood sugar stays between 70 and 180 mg/dL. The general goal for most adults with diabetes is at least 70% of the day in that range, which works out to roughly 17 hours out of 24.

The other targets matter just as much. You want less than 4% of the day between 54 and 69 mg/dL (the low zone) and less than 1% below 54 mg/dL (the dangerously low zone). On the high side, spending less than 25% of the day between 181 and 250 mg/dL is the benchmark. These percentages give a more complete picture of blood sugar control than any single finger stick can.