Blood pressure is measured in millimeters of mercury (mm Hg) and consists of two numbers, systolic and diastolic. A doctor uses these figures to categorize high blood pressure into stages.

Blood pressure measures the total amount of force your blood pushes against the walls of your arteries.

It measures two different pressures and is presented as two figures, one over the other:

  • Systolic (top): This measures the pressure of your blood on the artery walls as your heart beats.
  • Diastolic (bottom): This measures the pressure when your heart rests between beats.

Keep reading to learn more about how to read and interpret a blood pressure chart, as well as how to manage your blood pressure.

To manage your blood pressure, it’s important to know which blood pressure numbers are ideal and which ones are cause for concern.

High blood pressure (hypertension)

The table below outlines the ranges for healthy, elevated, or high blood pressure, as per the American Heart Association (AHA):

chart with blood pressure rangesShare on Pinterest

When looking at these numbers, notice that only one of them needs to be too high to put you in a hypertensive category.

For example, if your blood pressure is 119/81, you’d be considered to have stage 1 hypertension. If your blood pressure is 138/92, you’d be considered to have stage 2 hypertension.

Learn more about what is considered high blood pressure.

Low blood pressure (hypotension)

In general, meeting the criteria for hypotension has more to do with symptoms and specific situations than with exact numbers.

However, the AHA and the United Kingdom’s National Health Service (NHS) consider people hypotensive if their blood pressure falls within this range:

Systolic blood pressure (mm Hg)Diastolic blood pressure (mm Hg)Blood pressure category
90 or belowand 60 or belowHypotension

Blood pressure levels for children

Blood pressure levels are different for children than they are for adults. Children’s blood pressure targets are determined by several factors, like their age, sex, and height.

Talk with a pediatrician if you’re concerned about your child’s blood pressure. They can walk you through the charts and help you understand your child’s blood pressure.

There are several ways to measure your blood pressure.

A doctor can check your blood pressure in an office and many pharmacies offer free blood pressure monitoring stations.

You can also measure your blood pressure at home using home blood pressure monitors. These are available for purchase from pharmacies and medical supply stores.

The AHA recommends using an automatic home blood pressure monitor that measures blood pressure on your upper arm. Wrist or finger blood pressure monitors are also available but may not be as accurate.

It’s important to monitor your blood pressure regularly. Write the results in a blood pressure journal and share them with a doctor when you see them.

It’s also a good idea to take your blood pressure more than once per sitting, with 1 minute between each reading.

Learn more about how to measure your blood pressure at home.

After taking your blood pressure, it’s important to understand what your next steps are.

If your reading indicates low or high blood pressure, speak with a healthcare professional. They could help assess whether this is caused by an underlying health condition and develop an appropriate treatment plan.

For high blood pressure

Your management plan for high blood pressure will depend on several factors, such as the stage and type of hypertension and whether you’re living with an underlying health condition.

  • Stage 1 hypertension: A doctor may only recommend lifestyle and dietary changes. However, they may prescribe medications if you’re living with diabetes, heart disease, or kidney disease.
  • Stage 2 hypertension: A doctor will prescribe lifestyle and dietary changes and medications.
  • Hypertensive crisis: If your blood pressure is higher than 180/120 mm Hg, you should get immediate medical attention.

Your management plan may include a combination of:

Learn more about 18 ways to lower your blood pressure.

For low blood pressure

Your doctor may not treat low blood pressure if you don’t have symptoms.

Treatment options for low blood pressure may include:

Unmanaged low or high blood pressure may cause serious complications.

If your blood pressure is low

Low blood pressure may cause:

If your blood pressure is high

It’s hard to know when your blood pressure is high unless you’re monitoring it. High blood pressure doesn’t cause symptoms until you’re in a hypertensive crisis, which requires emergency medical care.

Left unmanaged, high blood pressure may cause:

Medical emergency

Call 911 or get immediate medical attention if you experience any of the following symptoms:

  • severe chest pain
  • back pain
  • difficulty breathing or speaking
  • numbness
  • weakness or fatigue
  • vision changes

What is a good blood pressure by age?

A healthy blood pressure for people ages 18 years and older is below 120/80 mm Hg.

What do the numbers mean in blood pressure?

A blood pressure reading provides two numbers. The top number measures systolic pressure, which is the amount of force your blood is pushing on your arterial walls while your heart is beating. The bottom number measures diastolic pressure, which is the force while your heart is resting between beats.

When should you worry about the bottom number of blood pressure?

Speak with a healthcare professional if the bottom number (diastolic) of blood pressure is 80 mm Hg or above. This is a sign of high blood pressure.

What is stroke-level blood pressure?

There is no precise blood pressure level for stroke, as it may occur in any stage of high blood pressure.

A blood pressure reading measures the pressure from your blood on your arterial walls while your heart is pumping.

A healthy blood pressure is below 120/80 mm Hg.

If you have low or high blood pressure, speak with a healthcare professional. They could help develop a treatment plan to help you manage your levels and lower your risk of developing complications.

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