Blood pressure values
Enter your systolic (top) and diastolic (bottom) readings taken at rest: instantly see which category they fall into, with the full reference table.
| Category | Systolic (mmHg) | Diastolic (mmHg) |
|---|---|---|
| Optimal | < 120 | and < 80 |
| Normal | 120–129 | and/or 80–84 |
| High-normal | 130–139 | and/or 85–89 |
| Grade 1 hypertension | 140–159 | and/or 90–99 |
| Grade 2 hypertension | 160–179 | and/or 100–109 |
| Grade 3 hypertension | ≥ 180 | and/or ≥ 110 |
How to read it
The classification (European ESC/ESH guidelines for office measurements) assigns the category based on the worse of the two values. Measure at rest, seated for 5 minutes, and average 2-3 readings.
Warning
A single high reading does not diagnose hypertension: averages over several days are what matter. This tool is informational only and does not replace your doctor.
How to measure, if you want a number that means something
Nearly all «high» readings taken at home are high because of how they were taken. The conditions the guidelines ask for are simple and nobody respects them: seated for at least five minutes, back supported, feet on the floor and legs uncrossed, arm resting at heart height, not talking during the measurement. No coffee, cigarettes or exercise in the previous half hour, and an empty bladder.
The right cuff size is the biggest source of error and the most ignored: too tight for the arm and it reads 10-15 mmHg higher. And the first reading doesn't count: you take two or three readings a minute apart and average the last two.
Why one reading isn't a diagnosis
Blood pressure isn't a fixed value: it varies by 20-30 mmHg through the day, rises with effort, with cold, with an argument and with the simple fact of being measured. The white coat effect — pressure that rises at the doctor's and not at home — affects one person in five, and the opposite exists too, pressure that's normal in the surgery and high in everyday life.
That's why a diagnosis is never made on one number: it's made on averages over several days, and where needed with automatic 24-hour monitoring. If an isolated value is high, the right thing is to repeat it for a few days at the same hour and take the numbers to the doctor — not to panic, and not to file it away either.
Home values are lower than surgery values
This is a detail that often confuses: the thresholds on this page, like all the classic ones, are those for measurement in the surgery. At home the same state of health gives slightly lower values, and the threshold matching 140/90 in the surgery is around 135/85. Comparing a reading taken on the sofa with the surgery table means judging yourself by the wrong yardstick.
Nearby tools
For body weight in relation to height there are BMI calculator and Waist-to-height ratio, which says more about cardiovascular risk than weight alone. For the units on lab reports there is Medical unit converter..