Blood Pressure Ranges: What Is Normal and What Is High?
Updated · 5 min read · By Taohidul Islam
Blood pressure is the force of blood pushing against the walls of your arteries. For adults, the American Heart Association (AHA) defines normal blood pressure as less than 120/80 mmHg, and high blood pressure (hypertension) as readings that are consistently 130/80 or higher. Because high blood pressure usually causes no symptoms, measuring it is the only way to know where you stand.
What do the two numbers mean?
A blood pressure reading is written as two numbers in millimeters of mercury (mmHg), such as 118/76:
- Systolic (top number): the pressure in your arteries when your heart beats.
- Diastolic (bottom number): the pressure in your arteries when your heart rests between beats.
Both numbers matter. Your category is set by whichever number falls in the higher category - so 135/78 counts as stage 1 hypertension because of the systolic number.
Blood pressure categories (American Heart Association)
These are the adult categories used by the AHA and the American College of Cardiology, and also by the CDC:
| Category | Systolic (mmHg) | Diastolic (mmHg) | |
|---|---|---|---|
| Normal | Less than 120 | and | Less than 80 |
| Elevated | 120 to 129 | and | Less than 80 |
| High blood pressure, stage 1 | 130 to 139 | or | 80 to 89 |
| High blood pressure, stage 2 | 140 or higher | or | 90 or higher |
| Severe hypertension (hypertensive crisis) | Higher than 180 | and/or | Higher than 120 |
A diagnosis is never based on one reading. Blood pressure changes from minute to minute with activity, stress, caffeine and even talking. A doctor looks at an average of readings taken on different occasions, and often asks for home readings too. Other countries use slightly different thresholds: the NHS, for example, generally treats 140/90 or higher in a clinic, or 135/85 or higher at home, as high.
When is a blood pressure reading an emergency?
If a reading is higher than 180/120: wait a few minutes and measure again. If it is still that high and you have any symptoms - chest pain, shortness of breath, back pain, numbness or weakness, a change in vision, or difficulty speaking - call emergency services right away. If it stays that high but you have no symptoms, contact your doctor promptly.
Also seek urgent care for sudden chest pain that does not go away, pain spreading to your arm, neck, jaw or back, or chest pain with sweating, nausea, light-headedness or breathlessness, whatever your last reading was.
Does high blood pressure cause symptoms?
Usually not. The CDC notes that high blood pressure typically has no warning signs, which is why many people do not know they have it. You cannot tell your blood pressure by how you feel, so headaches or dizziness are not a reliable guide in either direction. Regular checks, at a pharmacy, a clinic or at home, are what count.
Why high blood pressure matters
Over years, raised pressure strains the heart and damages blood vessels. According to the CDC, it increases the risk of heart disease, heart attack, heart failure, stroke and chronic kidney disease, and is linked to cognitive decline. The good news is that lowering high blood pressure reduces these risks, which is why finding it early matters.
What raises the risk of high blood pressure?
- Getting older
- Family history
- Eating a lot of salt (sodium)
- Low physical activity
- Carrying excess weight
- Drinking too much alcohol and smoking
- Conditions such as diabetes or kidney disease
- Long-term stress and poor sleep
How to measure blood pressure at home
Home readings can give you and your doctor a clearer picture than an occasional clinic check, but only if they are taken the same careful way each time. The AHA recommends a validated, automatic cuff that fits around your upper arm. Wrist and finger monitors are generally less reliable. Then:
- Avoid caffeine, exercise and smoking for 30 minutes before measuring, and empty your bladder.
- Sit quietly for 5 minutes with your back supported and feet flat on the floor, legs uncrossed.
- Rest your arm on a table so the cuff is at heart level, with the cuff on bare skin.
- Stay still and do not talk while the cuff inflates.
- Take two or three readings about a minute apart and note all of them.
- Measure at the same times each day, for example morning and evening, and keep a log.
Take your monitor to an appointment now and then so your doctor can check it reads in line with theirs.
Lifestyle habits that support healthy blood pressure
Health bodies agree on a short list of habits that help keep blood pressure in a healthy range:
- Eat less salt. The NHLBI's DASH eating plan sets a target of 2,300 mg of sodium a day and notes that 1,500 mg lowers blood pressure further.
- Follow a DASH-style diet rich in vegetables, fruit and whole grains, with low-fat dairy, fish, poultry, beans and nuts, and fewer sweets, sugary drinks and saturated fats.
- Move regularly. Brisk walking and other aerobic activity on most days helps. See our guide to how many steps a day for an easy starting point.
- Keep to a healthy weight, limit alcohol, and do not smoke.
- Sleep well and manage stress, both of which affect blood pressure.
If you have been diagnosed with high blood pressure, these habits work alongside, not instead of, the plan your doctor gives you. Never start, stop or change a blood pressure medicine without talking to your doctor.
When to talk to a doctor
- Your home readings are regularly in the elevated range or higher.
- You have not had your blood pressure checked in the last year (or as often as your doctor advises).
- You are pregnant and see a reading higher than usual.
- Your readings suddenly change, or you feel faint or dizzy on standing.
Logging your readings with FitRest
FitRest does not measure blood pressure. It gives you a quick way to log the readings you take with your own cuff, on iPhone or Apple Watch, and saves them to Apple Health. You can set reminders so you measure at the same times each day, see your readings over time, and export your log as a CSV or PDF to share with your doctor. FitRest does not diagnose or monitor any condition - it simply keeps your numbers in one place. Learn more on the health logs page.
Sources
FitRest is a wellness app, not a medical device. It does not diagnose, treat or prevent any condition. Talk to a qualified health professional about any health concern.