Normal blood pressure ranges
Pro Research Analysisby 
Searched over 200M research papers
Normal Blood Pressure Ranges: Key Definitions and Reference Values
Standard Blood Pressure Ranges in Adults
Normal blood pressure is generally defined as a systolic pressure (the top number) less than 120 mmHg and a diastolic pressure (the bottom number) less than 80 mmHg, often written as 120/80 mmHg. This value is widely accepted as the standard for healthy adults, though individual readings can vary due to factors like stress, activity, and time of day 210.
Ambulatory Blood Pressure Monitoring: 24-Hour, Daytime, and Nighttime Ranges
Ambulatory blood pressure monitoring, which measures blood pressure over 24 hours during normal daily activities, provides more detailed reference ranges. Meta-analyses of large studies show:
- 24-hour average: 115–120/70–75 mmHg
- Daytime average: 120–125/75–80 mmHg
- Nighttime average: 105–110/60–65 mmHg
The normal range (mean ± 2 standard deviations) for 24-hour blood pressure is about 97–139/57–87 mmHg, for daytime 101–146/61–91 mmHg, and for nighttime 86–127/48–79 mmHg 15.
Defining the Upper Limit of Normal Blood Pressure
Most guidelines and reviews agree that blood pressures above 140/90 mmHg are considered abnormal (hypertension), while values below 135/85 mmHg are considered normal for awake, ambulatory measurements . Some recent analyses suggest that lowering the upper limit for normal systolic blood pressure to below 130 mmHg may better identify individuals at lower risk for mortality, though this includes a smaller portion of the population .
Optimal Blood Pressure for Cardiovascular Health
Research consistently shows that lower blood pressure within the non-hypertensive range is associated with reduced risk of cardiovascular disease and mortality. An optimal blood pressure of 115/75 mmHg is linked to the lowest vascular risk, but such levels are uncommon in Western populations . For treated hypertensive patients, a target of less than 140/90 mmHg is often used, though lower targets may be beneficial for those at high risk, such as individuals with diabetes or kidney disease 29.
Blood Pressure Ranges in Special Populations
- Pregnancy: Normal blood pressure ranges change during pregnancy. For example, in Chinese pregnant women, the normal systolic range is about 94–119 mmHg at 12 weeks and 97–125 mmHg at 37 weeks, with diastolic ranges of 59–74 mmHg and 59–78 mmHg, respectively. These values can vary based on age and body mass index .
- Older Adults: Historically, higher blood pressure thresholds were considered normal for older adults, but current guidelines emphasize individualized assessment and risk-based targets 49.
Blood Pressure Variability and Risk
Not only the average blood pressure but also its variability over time is important. Higher fluctuations in systolic blood pressure are linked to increased cardiovascular risk, especially in younger individuals and those with lower baseline blood pressure .
Conclusion
Normal blood pressure for adults is typically considered to be less than 120/80 mmHg, with ambulatory monitoring providing more nuanced ranges. Blood pressures above 140/90 mmHg are generally considered abnormal, while optimal cardiovascular health is associated with even lower values, around 115/75 mmHg. Reference ranges may differ for special populations such as pregnant women and older adults. Both the average level and variability of blood pressure are important for assessing health risks.
Sources and full results
Most relevant research papers on this topic