Blood pressure category calculator

Below 120 systolic and below 80 diastolic mmHg, in the AHA/ACC classification used by both the 2017 and 2025 US guidelines. A systolic of 120 to 129 with diastolic under 80 is elevated, and 130/80 or higher is hypertension. The cut-offs apply to the average of repeated readings in adults, because any single measurement can run higher or lower than usual.

Stage 1 is a systolic of 130–139 mmHg or a diastolic of 80–89; stage 2 is a systolic of 140 or more or a diastolic of 90 or more. When the numbers disagree the higher category applies, so 128/92 is stage 2. The 2025 AHA/ACC guideline kept these thresholds and a general treatment goal below 130/80, and uses the PREVENT risk equations with a 7.5 % 10-year risk threshold when weighing medication for stage 1.

Above 180 systolic and/or 120 diastolic mmHg. The 2025 AHA/ACC guideline calls this severe hypertension when there is no sign of acute organ damage, replacing the older term hypertensive urgency, and a hypertensive emergency when there is, which needs monitored hospital treatment. A reading this high together with chest pain, shortness of breath, weakness, or changes in vision or speech is treated as an emergency.

Pulse pressure is systolic minus diastolic: 118/76 gives 42 mmHg. Mean arterial pressure, the average pressure across one heartbeat, is commonly estimated as diastolic plus one third of the pulse pressure, which gives 90 mmHg for 118/76. The one-third weighting reflects the heart spending about two thirds of each beat in diastole at resting heart rates, so the estimate is less exact at fast rates.

With a validated upper-arm device and a cuff of the right size, after a few minutes of quiet rest, seated with back and arm supported, the arm at heart level and no talking. The 2025 AHA/ACC guideline bases diagnosis on averaged readings taken this way, not on a single measurement, so several readings on different days give the value the categories are meant for.

정확도는 입력값과 계산 방법의 가정에 따라 달라집니다. 십진 연산은 유효숫자 50자리를 사용하지만, 추정값·수치해석 방법·원본 데이터의 정밀도는 더 낮을 수 있습니다. 표시값을 반올림해도 이러한 한계는 사라지지 않습니다. 독립적인 출처의 풀이와 대조한 계산 예시: 7. 예를 들어 “118/76”은 ACC/AHA 2017 Table 6: <120 and <80 is normal; MAP 76 + 42/3 = 90 (Python fractions)와 대조해 확인합니다.

Jones DW, Ferdinand KC, Taler SJ et al. 2025 AHA/ACC/AANP/AAPA/ABC/ACCP/ACPM/AGS/AMA/ASPC/NMA/PCNA/SGIM guideline for the prevention, detection, evaluation and management of high blood pressure in adults. Hypertension 2025;82(10):e212–e316; Whelton PK et al. 2017 ACC/AHA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. Hypertension 2018;71:e13–e115, Table 6 and §11.2; NHS — Low blood pressure (hypotension): below 90/60 mmHg.