How to Measure Your Blood Pressure at Home Correctly
The wrong posture can throw your reading off by 10–15 mmHg — enough to worry you for nothing, or to hide a real problem. A few minutes of preparation gives you a number you can trust.
But · 5 min read · Sep 5, 2026
Blood pressure changes constantly through the day — after a cup of coffee, after climbing the stairs, even while you sit impatiently waiting for the monitor. That is why a single reading rarely tells you much. What your doctor needs is a number measured properly, again and again over time.
Before you measure
- No coffee, strong tea, alcohol or cigarettes in the 30 minutes beforehand
- Use the bathroom first, because a full bladder can push the reading up by about 10 mmHg
- Sit quietly for 5 minutes — no talking, no scrolling on your phone
The right posture
Sit with your back against the chair, both feet flat on the floor, legs uncrossed. Rest your arm on a table so that the cuff is level with your heart. An arm hanging below heart level gives a falsely high number; an arm raised above it gives a falsely low one.
Wrap the cuff directly on the skin or over thin clothing, with the lower edge about 2 cm above the elbow. A cuff that is too tight or too loose for your arm is the most common source of error — if your upper arm is large, ask for a bigger size.
How many times, and when
Take 2 readings 1–2 minutes apart and average them. If the two differ by more than 5 mmHg, take a third.
Measure at two fixed times: in the morning before your medication and breakfast, and in the evening before bed. Record both so you can see your own daily blood pressure rhythm.
How to read the numbers
- Below 120/80 mmHg: normal
- 120–129 and below 80: slightly elevated, worth adjusting your lifestyle
- 130–139 or 80–89: stage 1 hypertension
- 140/90 and above: stage 2 hypertension, see a doctor
One reading above the threshold is not a diagnosis. Doctors usually need a series of readings over several consecutive days before drawing a conclusion.
When to go immediately
If your blood pressure is 180/120 mmHg or higher along with a severe headache, chest pain, shortness of breath, blurred vision or weakness on one side of the body, go to a medical facility right away — do not wait to measure again.
Record your readings in Health Tracking in the app so that at your next visit you can show your doctor the whole chart, instead of half-remembering a few numbers.
This information is for general reference only and does not replace advice from your doctor.
