Blood pressure categories
Categories follow the 2017 ACC/AHA guideline. A reading falls in the higher category if either number is over the line — 118/85 is stage 1 because of the diastolic.
| Category | Systolic | Diastolic | |
|---|---|---|---|
| Normal | below 120 | and | below 80 |
| Elevated | 120 – 129 | and | below 80 |
| High, stage 1 | 130 – 139 | or | 80 – 89 |
| High, stage 2 | 140 or more | or | 90 or more |
| Crisis | above 180 | and/or | above 120 |
Common questions
What's Mean Arterial Pressure and why is it shown?
MAP is roughly the average pressure in your arteries over one heartbeat cycle — calculated here as (systolic + 2 × diastolic) ÷ 3, since diastolic pressure lasts longer in the cycle than systolic. It's a number clinicians sometimes use alongside the two you already know.
Why does it reject readings where diastolic is higher than systolic?
Because that's not physiologically possible for a real reading — diastolic (the resting pressure) is always lower than systolic (the peak pressure). A higher diastolic number usually means the two were entered in the wrong fields.
For information only. A single reading cannot diagnose anything — talk to a doctor about readings that are consistently high or low.