A healthy blood pressure reading is below 120/80 mm Hg. That first number (systolic) measures the force when your heart beats, and the second (diastolic) measures the pressure between beats. Once either number climbs above those thresholds, your cardiovascular risk starts rising, even if you feel perfectly fine.
Blood Pressure Categories for Adults
The 2025 guidelines from the American Heart Association and American College of Cardiology break blood pressure into four categories:
- Normal: below 120/80 mm Hg
- Elevated: 120 to 129 systolic, with diastolic still below 80
- Stage 1 hypertension: 130 to 139 systolic or 80 to 89 diastolic
- Stage 2 hypertension: 140 or higher systolic or 90 or higher diastolic
If your systolic and diastolic numbers fall into two different categories, the higher category applies. So a reading of 135/75 counts as Stage 1 hypertension, even though the bottom number looks fine. These categories apply to all non-pregnant adults.
Why “Normal” Changed
Before 2017, anything under 140/90 was considered acceptable for most adults. The threshold dropped to 130/80 after large-scale trials showed that tighter control significantly reduced heart attacks, strokes, and death. The landmark SPRINT trial found that managing systolic pressure down toward 120 mm Hg, rather than the older 140 target, cut cardiovascular events and total mortality by roughly a third. Those findings reshaped guidelines and have held up through the most recent 2025 update.
Targets for Older Adults
Current guidelines recommend a systolic target below 130 mm Hg for adults 65 and older who live independently. That number surprises people who were told for years that blood pressure naturally rises with age and doesn’t need aggressive treatment. The evidence says otherwise. In the SPRINT trial, participants 75 and older who aimed for a systolic reading of 120 saw a 34% reduction in cardiovascular events and a 33% reduction in overall mortality compared to those with a standard target.
There’s a cognitive benefit too. Intensive blood pressure control in older adults reduced the occurrence of mild cognitive impairment by 19% and the combined risk of mild cognitive impairment or dementia by 15%. For older adults who can tolerate treatment without side effects like dizziness from standing up, tighter control pays off.
When Blood Pressure Is Too Low
There’s no single cutoff for “too low,” because some people walk around with a systolic reading of 90 and feel great. Low blood pressure becomes a problem when it causes symptoms. A drop of just 20 mm Hg, say from 110 down to 90, can trigger dizziness, fainting, blurred vision, fatigue, or trouble concentrating. If you’re consistently lightheaded when standing up or feeling foggy, your blood pressure may be dipping too far, especially if you’re on medication that lowers it.
Hypertensive Crisis: The Emergency Threshold
A reading of 180/120 mm Hg or higher is classified as a hypertensive crisis. If that number shows up alongside chest pain, shortness of breath, severe headache, blurred vision, or confusion, it’s a medical emergency. Without those symptoms, a single reading that high still warrants rechecking within a few minutes and contacting a healthcare provider promptly. Blood pressure at this level can damage blood vessels, the heart, kidneys, and brain in a short period of time.
Your Reading Might Not Be Accurate
Measurement errors are surprisingly large and remarkably common. Using a cuff that’s too small for your arm can inflate your reading by 5 to 20 mm Hg, enough to push a normal reading into the hypertension range. Skipping the recommended five-minute rest period before measurement adds another 10 to 20 mm Hg. Sitting on an exam table instead of a chair with back support can add 5 to 15 mm Hg. Even crossing your legs tacks on 5 to 8 extra points.
For the most reliable reading at home or in a clinic, sit in a chair with your back supported and feet flat on the floor. Rest your arm on a table at heart level. Use a properly sized cuff on bare skin, sit quietly for five minutes before measuring, and don’t talk during the reading. Take two or three readings a minute apart and average them.
White Coat and Masked Hypertension
About one in five people diagnosed with high blood pressure in a clinic actually have normal readings outside the office. This phenomenon, called white coat hypertension, shows up in roughly 20 to 25% of people referred for high blood pressure. The stress of a medical visit pushes readings higher than they normally run.
The opposite problem is more dangerous. Masked hypertension means your clinic readings look fine, but your blood pressure runs high the rest of the time. This affects an estimated 12 to 13% of adults, translating to roughly 17 million people in the U.S. alone. Because their office readings appear normal, these individuals often go undiagnosed and untreated. Home monitoring is the simplest way to catch either pattern. If your home readings consistently differ from clinic readings by 10 or more points in either direction, bring those numbers to your next appointment.
Blood Pressure in Children
Children’s blood pressure norms are more complicated than adults’ because healthy ranges depend on age, sex, and height. A number that’s perfectly normal for a tall 12-year-old boy might be elevated for a short 8-year-old girl. Pediatricians use percentile charts rather than fixed cutoffs. Generally, a child’s blood pressure should fall below the 90th percentile for their age, sex, and height group. Readings between the 90th and 95th percentile are considered elevated, and anything at the 95th percentile or above qualifies as hypertension. Your child’s doctor will plot their specific numbers on these charts during routine checkups.
What Pushes Blood Pressure Up
Sodium intake is the most direct dietary lever. Most adults consume well over 3,400 mg of sodium per day, far above the 2,300 mg or lower threshold that helps keep blood pressure in check. Excess weight is another major driver. Carrying extra body fat makes your heart work harder to push blood through additional tissue, and fat cells release substances that stiffen blood vessels. Physical inactivity, heavy alcohol use, chronic stress, and poor sleep all contribute independently.
Some causes aren’t lifestyle-related at all. Kidney disease, thyroid disorders, and certain medications (including common over-the-counter pain relievers and decongestants) can raise blood pressure. A strong family history also increases risk regardless of how well you eat or exercise. For most people, blood pressure creeps up gradually over years, which is why regular monitoring matters even when you feel healthy.