What’s a normal systolic and diastolic blood pressure?
Top 90 up to 120, bottom 60 up to 80. High is 140 or 90 at a clinic, and one alone counts. Which number says more about heart risk changes with age.
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What is a normal systolic and diastolic blood pressure?
Ideal is a top number of 90 up to 120 and a bottom number of 60 up to 80. Blood Pressure UK calls 90/60 up to 120/80 ideal, with a much lower risk of heart disease and stroke.
Systolic is the top number. Diastolic is the bottom one. Your monitor may label them SYS and DIA.
| Where it sits | Top (systolic) | Bottom (diastolic) |
|---|---|---|
| Low | Under 90 | Under 60 |
| Ideal | 90 up to 120 | 60 up to 80 |
| Above ideal, below high | 120 up to 140 | 80 up to 90 |
| High at a clinic | 140 or more | 90 or more |
| High as a home average | 135 or more | 85 or more |
Sources: Blood Pressure UK; NHS; NICE NG136
Only one number has to be out of line. Blood Pressure UK says a top number over 140 or a bottom number over 90 may mean high blood pressure, whatever the other number is.
Find the row for each of your numbers. Take the worse of the two.
What does my systolic number mean?
It’s the highest your blood pressure gets as your heart pumps blood around your body. The diastolic number is the lowest, as your heart relaxes between beats.
Both are in mmHg, millimetres of mercury. A top of 120 and a bottom of 80 is written 120/80, and said “120 over 80”.
- Below 90 mmHgLow.
- 90 up to 120 mmHgIdeal.
- Above 120 to just under 140 mmHgAbove ideal, below high.
- 140 to just under 180 mmHgHigh.
- 180 mmHg or aboveSevere. NICE: checks for organ damage as soon as possible.
Sources: Blood Pressure UK; NHS; NICE NG136
Top number over 140 with a normal bottom? Blood Pressure UK calls that isolated systolic hypertension (high blood pressure in the top number only) if it stays there. Read high systolic blood pressure next.
Want to know about a full reading, like 130/80 or 150/90? See what your blood pressure reading means.
Normal systolic but high diastolic: what does it mean?
It still counts as high. If the bottom number stays over 90 while the top is healthy, Blood Pressure UK calls it isolated diastolic hypertension.
Think of an MOT: fail on the brakes and it’s a fail, however good the lights are. A fail doesn’t mean the car will crash. Left unsorted, high blood pressure makes heart attacks and strokes more likely.
- Below 60 mmHgLow.
- 60 up to 80 mmHgIdeal.
- Above 80 to just under 90 mmHgAbove ideal, below high.
- 90 to just under 120 mmHgHigh, even with a normal top number.
- 120 mmHg or aboveSevere. NICE: checks for organ damage as soon as possible.
Sources: Blood Pressure UK; NHS; NICE NG136
One high reading isn’t a diagnosis. At a clinic, NICE says to take a second reading and record the lower of the last 2. If it’s between 140/90 and 180/120, a 24-hour or home monitor usually confirms it.
Bottom number 90 or more on more than one check? Book a GP check to confirm it.
Which number matters more, top or bottom?
It depends on your age. A US study followed 6,539 adults without heart disease, not on blood pressure tablets, for 20 years. The number that best predicted heart disease shifted as people got older.
| Age | Best sign of heart disease risk |
|---|---|
| Under 50 | The bottom number |
| 50 to 59 | Top, bottom and the gap between them, about equal |
| 60 to 79 | The gap between top and bottom. The top number counted more than the bottom. |
Source: Franklin et al, Circulation 2001
That’s the age switch from the top of the page. It shows which number predicted risk. It doesn’t mean you can ignore either one.
A bigger review pooled 61 studies of a million adults without heart disease or stroke at the start. Their risk of dying from heart disease or stroke rose steadily, with no clear cut-off down to 115/75. At ages 40 to 69, 20 higher on top was linked to about the same extra risk as 10 higher below.
So check both numbers each time, and write both down.
Does normal blood pressure change with age?
No. Blood Pressure UK says its chart suits adults of any age, as the cut-off doesn’t change with age. You’re just more likely to have high blood pressure as you get older, the NHS says.
Looking for an average? The one that counts is your home average.
NICE needs two things to confirm high blood pressure. First, a clinic reading of 140/90 or more. Then a home or daytime average of 135/85 or more over several days.
See how to measure blood pressure at home.
Got a high number? The NHS says lowering it even a small amount can help cut your risk.
Above ideal but not high? Blood Pressure UK suggests healthy changes to lower it.
Six NHS steps to help lower both numbers
- Aim for at least 150 minutes of exercise a week.
- Lose weight if you’re overweight.
- Avoid salty food and adding salt to your meals.
- Avoid drinking more than 14 units of alcohol a week on a regular basis.
- Cut down on caffeine, such as coffee, tea and cola.
- Don’t smoke.
Source: NHS: high blood pressure
For the moves that help most, see exercise for blood pressure.
When to speak to a GP
High blood pressure does not usually cause symptoms. Only a check shows it. Speak to a GP if:
- Your top number is 140 or more, or your bottom number 90 or more, at a pharmacy or clinic. Or your home average is 135/85 or more. Ask about confirming it.
- You’re 40 or over and haven’t had it checked for more than 5 years. Get it checked at a pharmacy or GP surgery.
- You keep getting symptoms of low blood pressure such as feeling light-headed or dizzy, feeling sick, blurred vision, weakness, confusion or fainting.
- Your clinic top number is 180 or more, or your bottom number 120 or more. NICE advises checks for organ damage as soon as possible. It advises a same-day specialist check if you also have new confusion, chest pain, signs of heart failure or sudden kidney damage, or bleeding or swelling at the back of the eye.
Get help from NHS 111 if you often have headaches or blurred vision, or chest pain that comes and goes. Also get help for other symptoms you’re worried could be from high blood pressure.
Call 999 for sudden chest pain or discomfort that doesn’t go away, such as squeezing, pressure, burning or indigestion. Also call for pain spreading to either arm, your neck, jaw, stomach or back. Or chest pain with sweating, feeling sick, light-headed or short of breath.
On tablets for blood pressure? Never stop or change a prescribed medicine without your prescriber. To see how your GP stages it, read stage 1 and stage 2 hypertension.