According to the American College of Cardiology (ACC) and American Heart Association (AHA), normal blood pressure is defined as a systolic reading below 120 mmHg AND a diastolic reading below 80 mmHg (i.e., less than 120/80). Readings consistently at or above these thresholds may warrant medical attention.

For most people, checking blood pressure once or twice a day at consistent times (e.g., morning and evening) is sufficient. Your doctor may recommend a specific monitoring schedule based on your health condition. It's best to measure at the same time each day, before meals and medication, for consistent tracking.

Systolic pressure (the top number) measures the pressure in your arteries when your heart beats and pumps blood. Diastolic pressure (the bottom number) measures the pressure when your heart rests between beats. For example, in a reading of 120/80 mmHg, 120 is systolic and 80 is diastolic.

Pulse pressure is the difference between your systolic and diastolic blood pressure (SBP minus DBP). A normal pulse pressure is typically between 40–60 mmHg. A consistently wide pulse pressure (above 60) may indicate increased cardiovascular risk, while a narrow pulse pressure can signal reduced cardiac output.

Regular logging helps you and your healthcare provider identify trends, evaluate the effectiveness of treatments or lifestyle changes, and detect potential issues early. A log provides a more comprehensive picture than occasional in-office readings, which can be affected by "white coat syndrome" (elevated readings due to anxiety in clinical settings).

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