How to Check Your Blood Pressure Correctly at Home

High blood pressure often has no symptoms, which is why it is called the silent killer. It raises the risk of heart attack, stroke and kidney disease. Checking your blood pressure at home gives a truer picture than a single reading at a clinic, where many people feel anxious and their numbers go up. But home readings are only useful if they are taken correctly.

Choosing a blood pressure monitor

• Choose an automatic upper-arm monitor. Wrist monitors are more sensitive to arm position and are less reliable for most people.
• Get the right cuff size. Measure around the middle of your upper arm. A cuff that is too small gives falsely high readings; too large gives falsely low readings.
• Look for a clinically validated model and a memory function to store readings.
• Take it to your next doctor’s visit once to compare it with the clinic machine.

You can compare options in our BP monitors section.

Before you measure

• Avoid tea, coffee, smoking and exercise for 30 minutes before.
• Empty your bladder.
• Sit quietly for 5 minutes in a chair with back support.

Step by step

1. Sit with your back supported, feet flat on the floor and legs uncrossed.
2. Rest your arm on a table so the cuff is at the level of your heart.
3. Put the cuff on bare skin, not over a sleeve, about 2 to 3 cm above the elbow crease.
4. Do not talk or use your phone while the machine is measuring.
5. Take two readings one minute apart and write down both, or use the average.

When and how often

When your doctor wants to assess your blood pressure, a common approach is to measure twice in the morning (before medicines and breakfast) and twice in the evening, for 7 days. Once your blood pressure is stable, checking a few times a week is usually enough, unless your doctor advises otherwise. Keep a simple log with the date, time and readings.

Understanding your readings

Blood pressure is written as two numbers, for example 120/80 mmHg. The top number (systolic) is the pressure when the heart beats; the bottom number (diastolic) is the pressure between beats.

• Below 120/80: normal
• Home average of 135/85 or higher: generally considered high at home, so discuss it with your doctor
• 180/120 or higher: very high; rest for 5 minutes and recheck

Home thresholds are slightly lower than clinic thresholds because readings at home tend to be lower.

When to get urgent help

If your reading is 180/120 or higher and you have chest pain, breathlessness, severe headache, weakness or numbness on one side, difficulty speaking or vision changes, go to the emergency department immediately.

Common mistakes

• Measuring straight after walking, climbing stairs or a cup of tea
• Letting the arm hang down or resting it too high
• Taking a single reading and panicking over one high number
• Changing or stopping medicines based on home readings without speaking to your doctor

Medicines and lifestyle

If you have high blood pressure, your doctor may prescribe medicines such as amlodipine or losartan. Take them every day at the same time, even when you feel well. Cutting down on salt, staying active, keeping a healthy weight, not smoking and managing stress all help lower blood pressure.

Key takeaways

• Use an upper-arm monitor with the correct cuff size.
• Sit quietly for 5 minutes, arm at heart level, and take two readings.
• A home average of 135/85 or more should be discussed with your doctor.
• Very high readings with symptoms need emergency care.

This guide is for general information and does not replace advice from a doctor.