What is normal blood pressure systolic and diastolic

Blood pressure is a measure of the force that your heart uses to pump blood around your body.

Table of Contents Show

How is blood pressure measured?
High blood pressure
Low blood pressure
Further information:
Find out how to understand blood pressure readings and use our blood pressure chart to see how healthy your blood pressure is.
What does a blood pressure reading look like?
The blood pressure chart
What do the readings mean?
Diagnosing high or low blood pressure
What is the normal value of systolic and diastolic pressure?
What is ideal blood pressure by age?
Which is more important in hypertension systolic or diastolic?
What does it mean when systolic pressure is high and diastolic is normal?

How is blood pressure measured?

Blood pressure is measured in millimetres of mercury (mmHg) and is given as 2 figures:

systolic pressure – the pressure when your heart pushes blood out
diastolic pressure – the pressure when your heart rests between beats

For example, if your blood pressure is "140 over 90" or 140/90mmHg, it means you have a systolic pressure of 140mmHg and a diastolic pressure of 90mmHg.

As a general guide:

ideal blood pressure is considered to be between 90/60mmHg and 120/80mmHg
high blood pressure is considered to be 140/90mmHg or higher
low blood pressure is considered to be 90/60mmHg or lower

High blood pressure

High blood pressure is often related to unhealthy lifestyle habits, such as smoking, drinking too much alcohol, being overweight and not exercising enough.

Left untreated, high blood pressure can increase your risk of developing a number of serious long-term health conditions, such as coronary heart disease and kidney disease.

Low blood pressure

Low blood pressure is less common. Some medicines can cause low blood pressure as a side effect. It can also be caused by a number of underlying conditions, including heart failure and dehydration.

Further information:

Cardiovascular disease (CVD)
Blood pressure test
Keep your blood pressure healthy
Blood Pressure UK
British Heart Foundation

Page last reviewed: 17 September 2019
Next review due: 17 September 2022

Find out how to understand blood pressure readings and use our blood pressure chart to see how healthy your blood pressure is.

What does a blood pressure reading look like?

When you have your blood pressure measured, you will be given two numbers, a top number and a bottom number.

Systolic blood pressure. This is the first, or top, number. This is the highest level your blood pressure reaches when your heart beats, forcing blood around your body.
Diastolic blood pressure. The second number, or bottom number, is the lowest level your blood pressure reaches as your heart relaxes between beats.

Blood pressure is measured in millimetres of mercury (mmHg). If the first number is 120 and the second number is 80, this would be written as 120/80mmHg, and you’d call it ‘120 over 80’.

This video explains more about systolic and diastolic blood pressure.

The blood pressure chart

Once you know your numbers, you can use the blood pressure chart to see what they mean and if your blood pressure is in the healthy range. The chart is suitable for adults of any age, as the cut-off point for diagnosing high blood pressure doesn’t change with age.

How to use the blood pressure chart

Simply find your top number (systolic) on the left side of the chart and your bottom number (diastolic) on the bottom. Where the two lines meet is your blood pressure.

Download the chart. Blood pressure chart for adults - PDF [PDF 121KB]

What do the readings mean?

As a general guide:

• 140/90mmHg or over – you may have high blood pressure
Most doctors use 140/90mmHg as the cut off for point for diagnosing high blood pressure (hypertension). This is the point where your risk of serious health problems goes up. They might prescribe medications and advise you to make changes to your lifestyle to bring your blood pressure down.

• 120/80mmHg up to 140/90mmHg – pre-high blood pressure
Also called high-normal blood pressure. This is not high blood pressure, but it is a little higher than it should be and means you could go on to develop high blood pressure. See how you can make healthy changes to your lifestyle to lower it.

• 90/60mmHg up to 120/80mmHg – ideal blood pressure
Also called normal blood pressure. Your blood pressure reading is healthy. At this level you have a much lower risk of heart disease and stroke. Following a healthy lifestyle will help you to keep it in the healthy range.

• 90/60mmHg or lower – you may have low blood pressure
Low blood pressure usually isn’t a problem, but it can sometimes make you feel faint or dizzy or could be a sign of another health problem.

The video below explains how your blood pressure numbers are linked to the risk of stroke and other disease.

Diagnosing high or low blood pressure

Only one of your numbers needs to be higher than it should be to be diagnosed with high blood pressure, and only one needs to be lower than it should be to be diagnosed with low blood pressure.

So if your top number is over 140 or the bottom number is over 90, you may be diagnosed with high blood pressure, regardless of the other number. If your top number is under 90 or your bottom number is under 60, you may be diagnosed with low blood pressure. Use the chart to see where your numbers sit.

If your top number (systolic pressure) is consistently higher than 140mmHg, but the bottom number is healthy - this is known as Isolated Systolic Hypertension. If the bottom number (diastolic pressure) is consistently higher than 90mmHg but the top number is healthy - this is known as Isolated Diastolic Hypertension.

Making sure your readings aren’t a one-off

A single high reading doesn’t necessarily mean you have high blood pressure, as many things can affect your blood pressure throughout the day, such as the temperature, when you last ate, and if you’re feeling stressed.

Your doctor or nurse will probably want to measure your blood pressure a number of times over a few weeks to make sure the reading wasn’t just a one off and that your blood pressure stays high over time.

Read about how high blood pressure is diagnosed, getting a blood pressure check, the further tests you might have if you have a high blood pressure reading, and what it means if you’re diagnosed with high blood pressure.

What is the normal value of systolic and diastolic pressure?

What is high blood pressure (hypertension)?.

What is ideal blood pressure by age?

Normal Blood Pressure By Age Both Male and Female.

Which is more important in hypertension systolic or diastolic?

Most studies show a greater risk of cardiovascular disease (especially strokes) related to high systolic pressure as opposed to elevated diastolic pressure.

What does it mean when systolic pressure is high and diastolic is normal?

If systolic blood pressure rises but diastolic blood pressure stays within an acceptable range, the condition is called isolated systolic hypertension.