• For the most accurate reading, take your blood pressure in the morning and evening.
• Take five minutes to get relaxed before you start taking your blood pressure.
• Follow our step-by-step guide from Harvard Medical School for how to take your blood pressure for the best results.
• This article was reviewed by Jason R. McKnight, MD, MS, a family medicine physician and clinical assistant professor at Texas A&M College of Medicine. 
• Visit Insider's homepage for more stories.

About one in three US adults have high blood pressure, or hypertension. However, you don't have to go to the doctor every single time to check your blood pressure — you can do it effectively at home. 

Regularly checking your blood pressure, whether you have high blood pressure or not, can help catch any major changes before they become serious. Here's how to do it yourself. 

How to take blood pressure at home 

A home blood pressure monitor enables you to take readings on your own. Devices range from arm cuffs to wrist cuffs and even watches — though Elaine Chin, MD, says the former is best. 

"The cuff that goes on the forearm is more standardized than a wrist version," says Chin. "It's all automatic. They're one button push devices and are very easy."

When taking your blood pressure at home, Chin recommends taking readings at two different points each day — morning and evening. Your doctor may recommend taking multiple readings per session, with a short break in between, to ensure accuracy. If you keep getting an unusual reading, you should follow up with your doctor. 

Blood pressure is notoriously higher in the morning, and research has found that morning blood pressure readings can be a better indicator of stroke risk than evening readings. In fact, a 2016 report in The American College of Cardiology Journal observed that morning blood pressure readings taken at home were stronger predictors of stroke and coronary artery disease risk than in-office doctor readings. 

"Make sure blood pressure is taken upon awakening, as soon as you roll out of bed, and make sure you're sitting," Chin says. "Keep doing the blood pressure monitoring around the same time each day." 

When taking your blood pressure at home, being relaxed and comfortable is key. Sitting quietly for five minutes before taking the reading — especially in the evening — can make it more accurate. Also, avoid drinking caffeine or smoking for at least 30 minutes prior to the reading, as these activities can boost your blood pressure. 

Once you're ready, here's a step-by-step guide from Harvard Medical School: 

• Sit upright on a firm chair with your arm level with your heart.
• Ensure your feet are firmly on the floor and don't cross legs. 
• Rest your arm on a table or counter. 
• Don't place the cuff over clothing: remove any shirt sleeves and make sure it's resting on your bare skin.
• Place the cuff just above the elbow, so it covers about 80% of your upper arm.
• Modern digital cuffs will provide instructions on what to do next. You may have to inflate the cuff manually or press a button to start the process. 
• Allow the cuff to deflate before you remove it, and wait five minutes between readings.

What is normal blood pressure 

According to the American Heart Association, a normal blood pressure reading is 120/80 mm Hg, though normal blood pressure ranges are different for children. 

The upper number, or the systolic reading, will be the first to increase with blood pressure, and greater than 120 is considered elevated. Hypertension occurs over 130 (stage 1) and 140 (stage 2) — this is time to speak with your doctor if you haven't already. Readings greater than 180/120 mm Hg may be a symptom of hypertensive crisis, and you should contact your physician or emergency services, especially if you also feel chest pain or shortness of breath. 

However, Chin says when you begin measuring at home, the first few days aren't always accurate. You may want to be extra careful until you get comfortable with the process.   "There is often anxiety when people first start to use their blood pressure cuff, which can make the numbers higher than it should be," says Chin.  

In addition to anxiety or stress, high blood pressure is often caused by a combination of unhealthy lifestyle factors, such as a high-sodium diet, lack of exercise, and smoking cigarettes. Chin suggests adopting the healthier DASH Diet, which she says can lower blood pressure in as little as two weeks. 

If you have high blood pressure, you should talk with your doctor about which lifestyle changes are the best for you, and how you can keep track of your progress. By routinely taking your blood pressure at home, you'll be able to ensure that your doctor-recommended lifestyle changes are having the impact they should. 

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