A blood pressure test checks if your blood pressure is healthy, or if it's high or low.
Blood pressure is the term used to describe the strength with which your blood pushes on the sides of your arteries as it's pumped around your body.
High blood pressure (hypertension) can increase your risk of developing serious problems, such as heart attacks and strokes, if it's not treated.
Having this quick test is the only way to find out what your blood pressure is – and it could save your life.
You should have a blood pressure test if you're worried about your blood pressure at any time.
If you're over 40, you can have this test done as part of an NHS Health Check, which is offered to adults in England aged 40 to 74 every 5 years.
If you have been diagnosed with high or low blood pressure, or you have a high risk of developing either, you may need more frequent checks of your blood pressure.
You can get your blood pressure tested at a number of places, including:
Blood pressure machines vary, but they're all a type of measuring device, which often have an arm cuff attached to it.
The cuff is usually wrapped around your upper arm and filled with air until it feels tight. This can feel uncomfortable but it only lasts a few seconds.
It's important to relax and not talk during this time, because this is when your blood pressure is measured.
If a healthcare professional is doing this for you, they may also use a stethoscope to record your blood pressure.
An automatic device usually picks up the measurements from sensors in the arm cuff, which are sent to a digital display.
You should get the results straight away.
Blood pressure is measured in millimetres of mercury (mmHg) and is given as 2 numbers:
The highest number is always the systolic pressure and it's always given first. For example, a blood pressure given as "120 over 80" or 120/80mmHg means a systolic pressure of 120mmHg and a diastolic pressure of 80mmHg.
As a general guide:
If your reading is between 120/80mmHg and 140/90mmHg, you may be at risk of developing high blood pressure. There are things you can do to help prevent high blood pressure.
Your GP may suggest 24-hour or ambulatory blood pressure monitoring (ABPM) if they think you may have high blood pressure (hypertension).
ABPM tests your blood pressure regularly over 24 hours, by using a cuff attached to a portable device that's worn on your waist.
You can continue with your daily activities during this time.
If you want to regularly check your blood pressure at home, you can buy a machine.
If you want to check your blood pressure regularly at home, you can buy a digital blood pressure machine.
Choose a machine that measures your blood pressure at your upper arm, not your wrist or finger.
Let your GP know you're doing this.