Table of contents
What is blood pressure?How to calculate blood pressureBlood pressure calculatorIs my blood pressure too high?What is hypertension?Is my blood pressure too low?ReferencesThis blood pressure calculator helps you to check if your blood pressure is within the recommended ranges by determining if your blood pressure is normal, too high, or too low. In the article below, you will find an explanation of how to calculate blood pressure, what factors can influence it, what hypertension is, and how to use our BP calculator.
If you want to compute the blood pressure for your child, you can visit our Pediatric blood pressure calculator.
What is blood pressure?
Blood pressure is the pressure of circulating blood on the walls of the blood vessels. It is usually determined by two values:
- Systolic blood pressure — the maximum BP during one heartbeat, when the heart contracts; and
- Diastolic blood pressure — the minimum BP in between two heartbeats, when the heart is at rest.
Systolic blood pressure is always higher than the diastolic measurement and is the first number you see in a blood pressure reading.
How to calculate blood pressure
Blood pressure is most commonly measured using a sphygmomanometer, which is also known as a blood pressure monitor or gauge. To make sure that your results are reliable, you should:
Sit still — make sure that you have been at rest for at least 5 minutes before the measurement and have not exercised for at least 30 minutes before;
Refrain from caffeine and cigarettes for at least 30 minutes before the measurement;
Sit correctly — your back should be straight and supported, and your arms should rest on a flat surface with the upper arm at heart level;
Always take the measurement at the same time of the day;
Take at least two measurements each time and record them somewhere; and
Always place the blood pressure monitor on your skin, do not take measurements over your clothes.
Blood pressure calculator
This blood pressure calculator uses two different guidelines, each with its own values for normal and abnormal blood pressure:
American — A Report of the American College of Cardiology (ACC) and American Heart Association (AHA) Task Force (2017).
European — Task Force of European Society of Cardiology (ESC) and the European Society of Hypertension (ESH) (2018).
The classification of normal blood pressure differs slightly depending on the guideline and should be lower than 120/80 mmHg (American guideline) or 130/85 mmHg (European guideline). Both guidelines also define intermediate thresholds, like elevated, high normal, and optimal blood pressure.
Is my blood pressure too high?
In adults, blood pressure can be considered high if it's greater than 130/80 mmHg or 140/90 mmHg, depending on the guideline. There are many risk factors related to high blood pressure:
Things you cannot change:
Family history of high blood pressure;
Age — the older you are, the more likely you are to have high blood pressure;
Gender — until the age of 64 men are more likely to suffer from hypertension, but after 65 this shifts to women;
Race — African-Americans tend to develop high blood pressure more often; and
Chronic kidney disease.
Thing you do have influence over:
Low level of physical activity;
Unhealthy diet, especially one that is high in sodium;
Being overweight or obese;
Overconsumption of alcohol;
Sleep apnea;
High cholesterol levels (use our cholesterol ratio calculator to determine if you have one);
Diabetes;
Smoking; and
Stress.
If your blood pressure exceeds the recommended values, your doctor can diagnose you with hypertension and prescribe appropriate medication.
What is hypertension?
Hypertension is a long-term condition in which the blood pressure is permanently elevated. It usually does not cause any symptoms but is considered a major risk factor for many diseases, including:
- Cardiovascular disease (to calculate your risk for developing severe complications, check out our CVD risk calculator);
- Vision loss;
- Dementia;
- Chronic kidney disease;
- Mitral regurgitation (to learn more about it, visit the EROA mitral regurgitation calculator).
Moreover, blood pressure that exceeds 180/120 mmHg can be considered a hypertensive crisis, and it is a life-threatening condition. Contact your doctor immediately.
Is my blood pressure too low?
A normal blood pressure is usually less than 120/80 mmHg, but can it be too low? Low blood pressure (hypotension) can be defined as blood pressure below 90/60 mmHg; however, some people have low blood pressure all the time, and it is normal for them. Therefore, doctors usually consider low blood pressure as dangerous if it causes noticeable signs and symptoms, such as:
- Dizziness, lightheadedness or nausea;
- Fainting;
- Dehydration;
- Lack of concentration;
- Blurred vision;
- Cold and pale skin; and
- Rapid and shallow breathing.
References
- Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines
- American Heart Association website
- The Task Force for the management of arterial hypertension of the European Society of Cardiology (ESC) and the European Society of Hypertension (ESH)
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