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’. The second number, or bottom number, is the lowest level your blood pressure reaches as your heart relaxes between beats.īlood pressure is measured in millimetres of mercury (mmHg). This is the highest level your blood pressure reaches when your heart beats, forcing blood around your body. When you have your blood pressure measured, you will be given two numbers, a top number and a bottom number.
What does a blood pressure reading look like? Find out how to understand blood pressure readings and use our blood pressure chart to see how healthy your blood pressure is.
