How to Check Blood Pressure at Home

Monitoring your blood pressure helps you manage your long-term health — but are you sure the results are accurate? Avoid these common mistakes to get more reliable readings.

Your blood pressure measures how hard your blood is pushing against the walls of your arteries as it’s pumped through your body by your heartbeats.

“Being aware of your blood pressure gives you insight into your heart health and can alert you of potentially undetected problems,” says Maria Kobylinski, MD, an internal medicine physician at Geisinger.

Because routine monitoring can help you and your doctor detect changes and help you keep your blood pressure at a healthy level, it’s smart to keep track. But you want to make sure you’re getting an accurate reading. Here’s how.

Common mistakes that skew your blood pressure reading

Even small missteps when measuring blood pressure can throw off your reading, whether at home or in the doctor’s office. These include:

Wrong cuff size
Incorrect arm placement
Legs crossed or feet dangling
Momentary stress (sometimes called “white coat syndrome”)

Research shows that your arm resting in your lap or hanging by your side can inflate your numbers by around 4 mmHg (millimeters of mercury — the standard unit of measurement for blood pressure). And if the blood pressure cuff is the wrong size, that can impact it by as much as 30 mmHg. “White coat syndrome,” or the temporary stress that some people feel in a clinical setting, can also skew your results.

Knowing how to correctly measure blood pressure could help keep you from being prescribed unnecessary medications due to misdiagnosed high blood pressure (also called hypertension).

Monitoring your blood pressure at home also means you’ll stay informed about your personal health baselines — it’s empowering to know what your normal blood pressure is.

How to check your blood pressure at home the right way

First, you’ll need an at-home blood pressure monitor. These devices are relatively inexpensive and available at most pharmacies. “Choose a monitor that fits on your upper arm, not your wrist,” says Dr. Kobylinski. “Many patients don’t realize this, but you can bring your monitor to your next doctor appointment to make sure it’s right for you. Your clinician can even teach you how to use it properly.”

Here’s how to correctly take your blood pressure at home:

Proper arm position: Arm placement is crucial. Your arm must be supported, such as resting on a desk, with the cuff positioned at about heart level on your arm. Do not let your arm rest in your lap or hang by your side when testing. “Always measure your blood pressure on your upper arm, above the elbow,” says Dr. Kobylinski.
Correct cuff size: Like Goldilocks, you may need to go on a quest to find a cuff that fits just right. Cuff sizes range from small to extra-large, but many at-home monitors are sold with only one size option — which may not be right for you. Your personal cuff size depends on your arm circumference. The American Heart Association recommends that the cuff be around 80% of the arm's circumference, and wide enough to cover 40% to 80% of the distance from the elbow to the shoulder.
Not too tight: Even when the cuff fits just right, correct placement and tightness is just as important. Make sure it’s tightly secure, but not uncomfortable. When the cuff inflates, you should be able to fit only two fingertips under its top edge, and your skin shouldn't pinch.
Skip the sleeves: Put the cuff on over your bare skin. Clothing underneath it could skew your results, particularly when you’re at home doing it yourself. If you need to roll up your sleeve, make sure it’s not so tight that your skin bunches, as this could affect your reading too.
Feet flat on floor: Never cross your legs when taking blood pressure, and don’t let your feet dangle above the floor when seated. For an accurate test, sit up straight but comfortably, with both feet resting flat on the floor. Relax for at least 5 minutes in this position before taking your reading.
Time it right: Avoid tobacco, caffeine and exercise 30 minutes beforehand. Time of day may also be a factor. “Blood pressure is usually highest in the morning and lowest during sleep,” says Dr. Kobylinski. That’s why you may be asked to measure twice a day, in the morning and evening.

How reliable are at-home blood pressure monitors?

“Using the right monitor for you and avoiding the common mistakes that can skew your readings should allow you to do fairly accurate tests at home,” says Dr. Kobylinski. Being in your familiar home environment can also help you sidestep the “white coat hypertension” of being tested in a clinic.

For extra accuracy, measure your blood pressure 2 or 3 times and use the average number for your records. Be sure to include the date and time of the test whenever recording your readings.

“It’s best to follow your doctor’s recommendations, and remember that home blood pressure monitoring is not a substitute for medical visits,” Dr. Kobylinski says.

How to read your blood pressure results

Your blood pressure measurements will include 2 numbers:

Systolic (top number) = pressure in blood vessels when the heart beats
Diastolic (bottom number) = pressure in blood vessels when heart relaxes between beats

The American Heart Association (AHA) categorizes 5 levels of blood pressure for most adults, with a normal reading being anything less than 120/80 mmHg.

Normal blood pressure	<120 mmHg systolic	<80 mmHg diastolic
Elevated blood pressure	120–129 mmHg systolic	<80 mmHg diastolic
High blood pressure (Stage 1)	130–139 mmHg systolic	80-89 mmHg diastolic
High blood pressure (Stage 2)	>140 mmHg systolic	>90 mmHg diastolic
Hypertensive crisis	>180 mmHg systolic	>120 mmHg diastolic

“For people over age 60, you want to aim for the systolic number to be less than 150 and the diastolic number less than 90,” says Dr. Kobylinski.

Tips for controlling high blood pressure

High blood pressure often has no signs or symptoms, but you can take steps to control it:

Take your medicine as directed
Eat lots of fresh fruits and low-fat dairy products
Limit saturated and total fat
Cut down on salt and sodium
Quit tobacco
Limit alcohol and caffeine
Maintain a healthy weight
Get regular exercise
Control stress

Benefits of tracking your blood pressure at home

It’s natural for your blood pressure to change over time. However, if you develop hypertension that’s left untreated, your risk of developing certain health issues can increase.

High blood pressure can lead to health issues including:

Heart attack
Stroke
Heart failure
Kidney failure

“If your blood pressure is suddenly extremely high, or has been consistently higher for a period of time, call your doctor,” says Dr. Kobylinski. “The longer your blood pressure remains high, the higher your risk for a heart attack or stroke.”

By measuring your blood pressure at home daily, you can become your doctor’s partner in staying on top of health issues so you can live a long and healthy life.