For healthcare professionals
Mean Arterial Pressure (MAP) Calculator
The mean arterial pressure is the average blood pressure during a single cardiac cycle. This tool estimates it from a systolic and diastolic reading and shows where it sits against the 65 and 70 mm Hg reference points used in published sepsis and surgery criteria. It is written for clinicians and is not a diagnosis.
Blood pressure reading
Use the systolic and diastolic values from the same reading. Nothing you enter leaves this page.
What you will see
The mean arterial pressure and whether it is under 65, 65 to under 70, or 70 mm Hg or more.
Educational only, not medical advice. Not a diagnosis. Decisions belong to the treating team.
Source
The formula as printed by Abassi M and colleagues, Open Forum Infectious Diseases 2025, open access (CC BY). Reference points: the Sepsis-3 consensus (Singer 2016), the SOFA score cardiovascular item (Lambden 2019) and Zhang K and colleagues, JMIR Aging 2025, open access (CC BY). The tests check the formula, that a value exactly on 65 or 70 counts in the higher band, and that a value below a cut-off is never displayed as the cut-off.
Validated in
Abassi 2025 used the formula in 686 Ugandan adults with HIV-associated cryptococcal meningitis. Zhang 2025 studied adults aged 65 or older having noncardiac surgery at two hospitals (35,262 and 13,418 patients). Sepsis-3 and the SOFA score concern adults with suspected or confirmed sepsis.
Limits
The formula is an estimate from a systolic and a diastolic value; it is not a direct measurement. The 65 and 70 mm Hg values come from specific settings (septic shock, the SOFA score, surgery under anesthesia) and are shown as reference points, not as general targets. The result does not tell you the cause of a low or high pressure.
The formula
MAP = 1/3 x systolic pressure + 2/3 x diastolic pressure (Abassi 2025). This is the same as diastolic + (systolic - diastolic) / 3.
Worked example: a reading of 120/80 mm Hg gives 80 + (120 - 80) / 3 = 93.3 mm Hg. A reading of 90/60 mm Hg gives 60 + 30 / 3 = 70 mm Hg, which the tool places in the 70 or more band.
The reference points
- 65 mm Hg. Sepsis-3 identifies septic shock in part by a vasopressor requirement to keep the MAP at 65 mm Hg or more, together with a serum lactate above 2 mmol/L despite adequate fluid resuscitation (Singer 2016). In surgery, 65 mm Hg is the most used intraoperative hypotension threshold (Zhang 2025).
- 70 mm Hg. In the SOFA score, a MAP under 70 mm Hg scores 1 point on the cardiovascular item, and higher points depend on vasopressor doses (Lambden 2019). In adults aged 65 or older having noncardiac surgery, Zhang and colleagues found that a MAP below 70 mm Hg was associated with major adverse cardiac events and concluded that intraoperative MAP should be kept above 70 mm Hg in this group (Zhang 2025).
The tool bands the unrounded value. A value of exactly 65 or 70 mm Hg counts in the higher band, and a value just below a cut-off is shown with extra decimals so it never looks equal to the cut-off.
Related tools
For a bedside sepsis prompt that includes systolic pressure, see the qSOFA calculator. To score organ dysfunction, including the MAP item, use the SOFA score calculator. The shock index calculator divides heart rate by systolic pressure. The pulse pressure calculator uses the same reading. Other bedside scores are listed under For healthcare professionals.
Sources
- Abassi M, Hou C, Fieberg A, et al. Cerebral perfusion pressures and implications on clinical outcomes and medical management in cryptococcal meningitis. Open Forum Infect Dis. 2025;12(8):ofaf451. doi:10.1093/ofid/ofaf451. Open access (CC BY). Methods (MAP = 1/3 x SBP + 2/3 x DBP, the average blood pressure during a single cardiac cycle). pmc.ncbi.nlm.nih.gov/articles/PMC12359033/
- Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801-810. doi:10.1001/jama.2016.0287. PMID 26903338. Abstract (SOFA-based definitions of sepsis and septic shock), Box 4 (qSOFA criteria) and section on screening for patients likely to have sepsis. pmc.ncbi.nlm.nih.gov/articles/PMC4968574/
- Lambden S, Laterre PF, Levy MM, Francois B. The SOFA score: development, utility and challenges of accurate assessment in clinical trials. Crit Care. 2019;23:374. doi:10.1186/s13054-019-2663-7. PMID 31775846. Open access (CC BY). Table 1 (SOFA criteria) and the sections on development, calculation, the CNS component and defining sepsis. pmc.ncbi.nlm.nih.gov/articles/PMC6880479/
- Zhang K, Liu C, Wang M, et al. Intraoperative hypotension and major adverse cardiac events among older adult patients undergoing noncardiac surgery: retrospective cohort study. JMIR Aging. 2025;8:e67177. doi:10.2196/67177. Open access (CC BY). Abstract (results and conclusions) and Discussion (65 mm Hg as the most used intraoperative hypotension threshold). pmc.ncbi.nlm.nih.gov/articles/PMC12530642/
Written and maintained by the uncovermyrisk.com editorial team. We do not have a medical reviewer; every claim links to its primary source above. Last reviewed: 2026-11-02. Spotted an error? See About.