Normal blood pressure is a reading below 120/80 mm Hg. That means the top number (systolic) is less than 120 and the bottom number (diastolic) is less than 80. These thresholds were reaffirmed in the 2025 joint guidelines from the American Heart Association and American College of Cardiology.
What the Two Numbers Mean
A blood pressure reading always has two numbers. The top number, systolic pressure, measures the force your blood exerts against artery walls when your heart beats and pushes blood out. The bottom number, diastolic pressure, measures that force when your heart rests between beats. Both are recorded in millimeters of mercury (mm Hg), which is simply the unit used to measure pressure.
Of the two, the top number tends to matter more for predicting heart disease and stroke, especially once you’re over 50. That said, both numbers factor into your overall category.
Blood Pressure Categories for Adults
Your reading falls into one of five categories:
- Normal: Below 120 systolic and below 80 diastolic
- 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
- Hypertensive crisis: Higher than 180 systolic and/or higher than 120 diastolic
Only one number needs to be high for you to move into a higher category. If your systolic is 135 but your diastolic is 75, that’s still Stage 1 hypertension because of the top number alone.
Elevated blood pressure (120 to 129 over less than 80) is a warning zone. It’s not yet hypertension, but without changes it often progresses there. People in this range typically benefit from lifestyle adjustments like more physical activity, less sodium, and better sleep.
European Guidelines Use a Different Cutoff
If you’ve seen conflicting numbers online, there’s a reason. European guidelines from the European Society of Cardiology set the hypertension threshold at 140/90, not 130/80. They define “elevated blood pressure” as anything from 120 to 139 systolic or 70 to 89 diastolic, treating this as a single broad category rather than splitting it into elevated and Stage 1 the way U.S. guidelines do.
The European guidelines also avoid calling any reading “normal.” Their reasoning is that cardiovascular risk begins to rise at blood pressures as low as 90 systolic, so even numbers well within the healthy range aren’t truly risk-free. In practical terms, though, a reading under 120/80 is considered ideal on both sides of the Atlantic.
Normal Ranges Are Different for Children
The adult thresholds don’t apply to kids. In children and teens, normal blood pressure is defined as a reading below the 90th percentile for their age, sex, and height. A 5-year-old boy of average height, for example, typically has a systolic reading around 90 to 98 and a diastolic reading around 50 to 55. By age 17, those numbers climb to roughly 114 to 122 systolic and 65 to 70 diastolic, approaching adult levels. Girls follow a similar pattern but run slightly lower at most ages. Your child’s pediatrician uses standardized growth-based charts to determine whether a specific reading is concerning.
Why Your Reading Can Vary
Blood pressure isn’t a fixed number. It fluctuates throughout the day based on activity, stress, caffeine intake, hydration, and even the temperature of the room. A single high reading doesn’t necessarily mean you have hypertension, and a single normal reading doesn’t guarantee you’re in the clear. What matters is your pattern over multiple readings taken under consistent conditions.
How to Get an Accurate Reading
The way you sit during a measurement can shift your numbers by 10 points or more. The CDC recommends the following for an accurate reading:
- Sit in a chair with your back supported for at least five minutes before measuring.
- Keep both feet flat on the floor with legs uncrossed.
- Rest your arm on a table so the cuff sits at chest height.
- Place the cuff on bare skin, not over clothing, and make sure it’s snug without being tight.
If you’re monitoring at home, follow the same routine each time. Empty your bladder first, skip caffeine and exercise for 30 minutes beforehand, and sit quietly for five minutes before starting. Home readings are often more reliable than office readings because you can control the environment and avoid the anxiety that sometimes spikes numbers in a clinical setting (often called “white coat hypertension”).
When a Reading Is an Emergency
A blood pressure of 180/120 or higher is a hypertensive crisis. If that reading comes with chest pain, shortness of breath, blurred vision, or stroke symptoms like sudden numbness or trouble walking, call 911. If you see a number that high but feel fine, wait five minutes, recheck, and contact your doctor promptly if it stays elevated. Not every spike at this level causes immediate organ damage, but it always requires medical attention.