Blood pressure chart.
The American Heart Association defines five blood pressure categories. Here is what each range means and what to do if your reading falls there.
Source: American Heart Association 2025 guidelines.
AHA blood pressure ranges.
These ranges apply to adults age 18 and older. Both numbers matter. If either is in a higher category, that is your classification.
Under 120 / Under 80 mmHg
MeansYour blood pressure is in a healthy range.
DoKeep doing what you are doing. Check again in 1 to 2 years.
120 to 129 / Under 80 mmHg
MeansHigher than normal but not yet hypertension. This used to be called prehypertension.
DoMake lifestyle changes now. Cut sodium, exercise more, manage your weight. No medication in most cases yet.
130 to 139 / 80 to 89 mmHg
MeansHypertension. Your cardiovascular risk is elevated.
DoTalk to your doctor. Lifestyle changes are step one. Medication may be added based on your overall health profile.
140 or higher / 90 or higher mmHg
MeansHigh blood pressure that usually needs medication alongside lifestyle changes.
DoSee your doctor soon. Medication plus lifestyle changes is the standard approach. Regular monitoring is essential.
Over 180 / Over 120 mmHg
MeansA medical emergency.
DoWait a minute and take it again. If it is still that high, call 911 if you also have symptoms, or contact your doctor right away if you do not.
Under 90 / Under 60 mmHg
MeansHypotension. May be normal or may cause dizziness and fainting.
DoIf you have symptoms like dizziness or fainting, talk to your doctor. Dehydration, medication, and certain conditions can cause low BP.
Source: American Heart Association. Last updated 2025. Always consult your doctor for personal medical advice.
How to read your number.
Your blood pressure is written as two numbers separated by a slash. For example, 128/82. The top number (128) is systolic. The bottom number (82) is diastolic.
Look up each number in the chart above. Whichever falls in the higher category is your classification. In the example above, 128 is Elevated and 82 is Stage 1. That reading is Stage 1 Hypertension.
One reading does not tell the whole story. The AHA recommends taking readings twice a day for at least a week before drawing any conclusions. Your home average is more reliable than a single clinic reading.
White coat hypertension is real. Many people read higher in a doctor's office than at home. The AHA says home monitoring is the most accurate way to know your true blood pressure.
What the two numbers are
The top number: systolic
The pressure in your arteries while the heart is squeezing. It is the higher of the two, and it is the one that moves most when you are startled, rushing or holding a conversation with the cuff on.
The bottom number: diastolic
The pressure that remains between beats, while the heart is refilling. It is the lower of the two and it is steadier.
They are written top over bottom, so 128 over 82 means a systolic of 128 and a diastolic of 82. Both are measured in millimetres of mercury, written mmHg, which is a hangover from the mercury columns the first instruments used.
What if the two numbers land in different rows?
Then the higher row is the one that counts. This is not a separate rule somebody added. It falls out of how the categories are written.
Top number, systolic
Bottom number, diastolic
Two separate scales, systolic above and diastolic below. The bands do not line up, which is exactly why a reading can sit in two different rows at once.
Look at the wording. Elevated is 120 to 129 / under 80 — it needs the top number and the bottom number to both be in range. But High, stage 1 is 130 to 139 / 80 to 89, and High, stage 2 is 140 or higher / 90 or higher — those need only one of the two.
So a reading of 140 over 70 is stage 2, on the top number alone. A reading of 118 over 84 is stage 1, on the bottom number alone. The category is decided by whichever number has climbed furthest, not by an average of the two and not by the bigger-looking digit.
Which number matters more? Both are used, which is why both appear in the categories, and a chart cannot rank them for you as an individual. What the chart does say is that either one on its own is enough to move the row, so neither can be waved away because the other looks fine.
Is there a different chart for my age?
No. The categories above are the adult categories, and they do not change at 40, 60 or 75.
You will find charts online offering a “normal blood pressure by age” table with a different target for every decade. Those are not published by the American Heart Association and we are not going to reproduce one, because a table that quietly raises the bar as you get older tells an older reader their rising numbers are fine when the guidance says no such thing.
What is true is that blood pressure does tend to rise with age, and that systolic tends to rise more than diastolic. That is a description of what happens to populations. It is not a licence to move your own target, and what to do about a number is a decision for a clinician who knows the rest of your history.
The same goes for separate charts by sex. The adult categories are the adult categories.
What this chart does not tell you
A table with your number in it feels like an answer. It is a lookup, and there are at least five things it cannot do.
- It does not diagnose you. A category is where one measurement falls. High blood pressure is diagnosed by a clinician from repeated measurement and the rest of your history, not from a row on a chart.
- It does not decide anything about medication. Nothing about starting, stopping or changing a medicine follows from a category. That is a conversation with a doctor and this site will never have an opinion on it.
- It does not explain why a reading changed. Coffee, a rushed morning, a full bladder, talking during the measurement, the wrong cuff size. The chart cannot see any of that.
- It does not prove your monitor is right. A number in a row is still a number your device produced. Whether the device was ever tested for accuracy is a separate question with a separate answer.
- It does not replace being examined. The chart knows two numbers. A clinician knows you.
One reading is not a pattern
Blood pressure moves all day. It is lower asleep, higher after climbing stairs, and it reacts to a conversation. Any single reading is one sample of something that never stops moving, which is why the categories talk about readings being consistently in a range.
The joint statement from the American Heart Association and the American Medical Association describes 2 readings at least 1 minute apart, morning and evening, over 7 days. That is 28 readings, and it is the set worth putting on a chart rather than any one of them.
American Heart Association and American Medical Association, Self-Measured Blood Pressure Monitoring at Home: A Joint Policy Statement, Circulation. 2020;142(4):e42-e63.
If a reading looks wrong, check the measurement before you believe it
A surprising number at home is often a measurement problem rather than a blood pressure problem. Three things account for most of it, and all three are fixable.
- The cuff is the wrong sizeThe single biggest one. A cuff that is too small reads high, and on a large arm it can be high by a lot.
- The setup was offCrossed legs, an unsupported back, a full bladder, coffee half an hour ago, or talking while it ran.
- The monitor was never testedBeing cleared for sale and being tested for accuracy are different things, and most people assume they are the same.
Range chart source: American Heart Association, Understanding Blood Pressure Readings, last reviewed 14 August 2025. The 2025 ACC/AHA guideline kept these categories and the 130/80 threshold unchanged from 2017.
Common questions.
What is a normal blood pressure reading?
Normal is under 120 systolic and under 80 diastolic, written as 120/80 or lower. If your reading is in this range, your risk is low. The AHA recommends checking again in one to two years if you have no other risk factors.
What is a good blood pressure for my age?
The AHA uses the same five categories for all adults. However, blood pressure does tend to rise with age. What matters most is whether your individual trend is stable or climbing. Tracking at home over weeks gives a better picture than one office reading.
What causes high blood pressure?
Most high blood pressure has no single cause. Risk factors include high sodium intake, low physical activity, being overweight, heavy alcohol use, smoking, chronic stress, poor sleep, and family history. Some medications and conditions can also raise it.
How often should I check my blood pressure at home?
The AHA recommends checking twice a day for the first week, then twice a week once you have a baseline. Morning and evening readings are most useful. Take two readings at least a minute apart and average them.
What does it mean if only my top number is high?
Isolated systolic hypertension is when systolic is 140 or above but diastolic is under 90. It is common in older adults and is a real form of hypertension. It carries the same cardiovascular risks and should be discussed with your doctor.
Can blood pressure vary throughout the day?
Yes. Blood pressure naturally dips during sleep and rises after waking. It also responds quickly to stress, caffeine, exercise, posture, and temperature. This is why tracking at home over time is more accurate than a single clinic reading.
Know which category you are actually in.
BP Central logs your readings and shows the range each one falls in. Keep it up and watch the trend build over 7, 30 and 90 days.
The chart tells you what a reading means. A run of readings tells you what is actually going on, and BP Central is where you keep them.
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