How to measure blood pressure at home
Why a reading is taken matters as much as what it says: the same arm, on the same afternoon, can produce meaningfully different numbers depending on whether someone sat quietly first. Everything below is quoted from the American Heart Association’s published instructions, with the source next to each one.
None of this is this site’s advice. bpmeter has no clinical author and no clinical reviewer. This page reproduces what a named organisation publishes, linked and dated, so you can check it at the source and take anything specific to your own situation to a health care professional.
Before the reading
“Don't smoke, drink caffeinated beverages or exercise within 30 minutes before taking your blood pressure.”
“Empty your bladder.”
“Allow at least five minutes of quiet rest before measurements.”
How to sit
“sit in an upright position with back supported, feet flat on the floor and your arm supported at heart level”
“Support your arm on a flat surface and make sure it is at heart level (prop a pillow underneath your arm if needed).”
“Don't talk or use the phone.”
Where the cuff goes
“The middle of the cuff should be placed on the upper arm at heart level. The bottom of the cuff should be placed directly above the bend of the elbow on your bare skin, not over clothing.”
“You can use either arm. Usually there is not a big difference between readings on them.”
How many readings, and when
“Each time you measure, take two readings one minute apart.”
“Measure at the same time every day.”
On what a single number is worth, the same organisation is blunt:
“Blood pressure fluctuates a lot, so a patient shouldn't worry about one high reading.”
That is the argument for keeping a log rather than reacting to any one afternoon. Print a blank log sheet or keep one in this browser.
The monitor itself
“The American Heart Association recommends an automatic, cuff-style, upper arm (biceps) monitor.”
This site does not rate, rank or sell monitors, and has no arrangement with anyone who makes them. On the class of device the guideline singles out, the 2025 AHA/ACC Guideline for the Prevention, Detection, Evaluation and Management of High Blood Pressure in Adults says:
“Reliance on cuffless devices, including smartwatches, for accurate blood pressure measurements should be avoided until these devices demonstrate greater precision and reliability.”
More on what that means for watch readings, including why this site will not import them.
Once you have a reading
The calculator shows where two numbers fall in the guideline’s published table, along with pulse pressure and estimated mean arterial pressure. It runs in your browser and the reading is never sent anywhere.