Heart health
Understanding your blood pressure numbers
What the top and bottom numbers mean, and how to measure at home properly.
A blood pressure reading has two numbers. The top number is systolic pressure — the pressure when your heart contracts. The bottom number is diastolic pressure — the pressure when your heart relaxes between beats.
What the numbers mean
For most adults, a reading around 120/80 mmHg is considered normal. Consistently higher readings may indicate elevated blood pressure, but one high reading is not a diagnosis. Your doctor will look at repeated measurements, taken at rest, over time.
Measure at home correctly
Sit quietly for five minutes, keep your back supported and your feet flat, and rest your arm at heart level. Avoid caffeine, exercise and smoking for 30 minutes beforehand. Take two readings a minute apart and record them.
When to seek advice
If your readings are repeatedly high, or you have headaches, chest pain, breathlessness or visual changes, speak to a doctor promptly. High blood pressure often has no symptoms, which is why regular checks matter.
This article is general information and is not a substitute for medical advice. Speak to a doctor about your own situation.