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What the numbers mean.

Short, plain explanations of blood pressure ranges and the terms you will hear. Each one names its source so you can go and read it yourself. None of it tells you what to do about your own readings. That part is your doctor's job.

The ranges

These are the categories on the American Heart Association chart. A category describes one reading. It does not describe a person, and it is not a diagnosis.

  • Normal
    Under 120 / under 80
  • Elevated
    120 to 129 / under 80
  • High, stage 1
    130 to 139 / 80 to 89
  • High, stage 2
    140 or higher / 90 or higher
  • Crisis range
    Over 180 and/or over 120

Values in mmHg. For stage 1 and stage 2, either number on its own is enough to put a reading in that row. Source: American Heart Association, Understanding Blood Pressure Readings, last reviewed 14 August 2025.

If a reading is over 180 or over 120

The American Heart Association asks you to wait one minute and take it again. If it is still that high and you have chest pain, shortness of breath, back pain, numbness, weakness, a change in vision or trouble speaking, call 911. If it is still that high and you do not have those symptoms, contact your health care professional.

What is in the app

The Learn tab in BP Central holds seven short articles. Each one explains what a term means, why it matters when you are recording at home, and where the information came from. That is the whole list. We would rather ship seven we can stand behind than twenty five we cannot.

Normal blood pressure

Less than 120 over less than 80 mmHg.

Elevated

120 to 129 over less than 80 mmHg.

Stage 1 range

130 to 139, or 80 to 89 mmHg.

Stage 2 range

140 or higher, or 90 or higher mmHg.

Severe range

Higher than 180 and/or higher than 120 mmHg.

White-coat hypertension

Higher in a medical office than outside it.

Masked hypertension

Not high in a medical office, higher outside it.

The app does not hold a drug reference and gives no treatment guidance. If you want to know what a medicine does or whether to take one, that is a conversation with your doctor or pharmacist.

Getting a reading you can trust

Blood pressure measured at a surgery and blood pressure measured at home can differ by a lot, which is why home readings are worth keeping. It also means how you take them matters. Resting first, sitting properly, and putting the cuff on bare skin all change the number you get.

Read the home measurement checklist

Sources: American Heart Association and American Medical Association. Self-Measured Blood Pressure Monitoring at Home: A Joint Policy Statement. Circulation. 2020;142(4):e42-e63. And American Heart Association. Measurement of Blood Pressure in Humans: A Scientific Statement From the American Heart Association. Hypertension. 2019;73(5):e35-e66.

Keep your own record

BP Central saves every reading, shows the range it falls in, and builds your trend over 7, 30 and 90 days. First 10 readings free, then $6.99 once.

When you are ready to start recording, BP Central keeps your readings and works out the averages.

Coming to Google Play

First 10 readings free. Then $6.99 once. No subscription. iPhone.

Or start with the checklist

We only ask for your email. We never ask for your readings, and your app data is never used for email.

BP Central keeps a record of readings you enter yourself. It does not measure your blood pressure and it is not medical advice. One reading at home does not diagnose anything. Only a doctor or other health professional can do that.