平均动脉压（MAP）计算器

关于此计算器

This calculator estimates your mean arterial pressure (MAP) from a single blood-pressure reading and places that reading in a standard blood-pressure category. MAP is the average pressure pushing blood through your arteries across one heartbeat — a useful single number for gauging whether your organs are being adequately perfused. Enter your systolic (top) and diastolic (bottom) numbers in mmHg to see your MAP, pulse pressure, and category.

如何解读你的结果

The headline is your blood-pressure category, shown on a green-to-red gauge that runs Normal → Elevated → Stage 1 → Stage 2 → Crisis. The category is decided by the higher of your two numbers: because the Stage 1, Stage 2, and Crisis bands use an OR rule, a normal-looking systolic with a raised diastolic (or vice versa) still lands in the higher band. That is why 120/80 reads as Stage 1, not Normal — the diastolic 80 sits in the 80–89 Stage 1 range. Mean arterial pressure and pulse pressure are shown as secondary metrics: a MAP of 70–100 mmHg is the usual normal range, and a pulse pressure near 40 mmHg is typical. A Crisis result (above 180/120) triggers an emergency-care banner.

计算方法

Mean arterial pressure is computed as MAP = (SBP + 2 × DBP) / 3, rounded to two decimal places — algebraically identical to DBP + ⅓ × (SBP − DBP). Pulse pressure is SBP − DBP; it is normally about 40 mmHg, called wide at 60 mmHg or more, and narrow when below about one quarter of the systolic value. The MAP zone is read as below the perfusion floor under 60 mmHg, low at 60–69 mmHg (note the 65 mmHg sepsis target), normal at 70–100 mmHg, and high above 100 mmHg. Blood-pressure categories follow the 2017 ACC/AHA guideline, evaluated from the highest band down so the higher category always wins on split readings: Crisis when SBP > 180 or DBP > 120; Stage 2 when SBP ≥ 140 or DBP ≥ 90; Stage 1 when SBP is 130–139 or DBP is 80–89; Elevated when SBP is 120–129 and DBP < 80; otherwise Normal. The ESC 2024 toggle instead defines Elevated as 120–139/70–89 mmHg and Hypertension as ≥ 140/90 mmHg.

实例演示

A reading of 120/80 mmHg, classified with the ACC/AHA 2017 guideline.

MAP = (120 + 2 × 80) / 3 = 280 / 3 = 93.33 mmHg, which is within the 70–100 normal range. Pulse pressure = 120 − 80 = 40 mmHg (normal). The blood-pressure category is Hypertension Stage 1, not Normal, because the diastolic value of 80 falls in the Stage 1 band (80–89) and the OR rule selects the higher category.

常见问题

What is a normal mean arterial pressure?

A MAP of roughly 70–100 mmHg is generally considered normal. At least about 60 mmHg is needed to perfuse vital organs, and clinicians often target at least 65 mmHg in septic shock (the Surviving Sepsis Campaign target). These are general references, not personal goals — your clinician sets targets for your situation.

Why does this calculator label 120/80 as Stage 1 instead of Normal?

Under the 2017 ACC/AHA blood-pressure categories, a diastolic reading of 80 already sits in the Stage 1 band, which runs 80–89 mmHg. The systolic and diastolic numbers are combined with an OR rule and the higher category wins, so 120/80 is classified as Hypertension Stage 1. A single reading like this is not a diagnosis — hypertension is confirmed across multiple readings on different days.

How is mean arterial pressure calculated?

MAP is estimated as (SBP + 2 × DBP) / 3, which is the same as DBP + ⅓ × (SBP − DBP). Diastole is weighted twice because, at a normal resting heart rate, the heart spends about two-thirds of each cardiac cycle in diastole. The formula is an estimate that assumes a resting heart rate; at very high heart rates the true average drifts toward (SBP + DBP) / 2.

What is the difference between the ACC/AHA and ESC guidelines?

The US ACC/AHA 2017 guideline diagnoses hypertension at 130/80 mmHg and uses five bands (Normal, Elevated, Stage 1, Stage 2, Crisis). The European ESC 2024 guideline defines an Elevated band of 120–139/70–89 mmHg and diagnoses hypertension at 140/90 mmHg. The same reading can carry a different label: 135/85 is Stage 1 in the US but Elevated under ESC. Use the toggle to switch between them.

Is this calculator a medical diagnosis?

No. It is an informational estimate only. Blood pressure should be measured by a trained professional, with the correct cuff size and technique, and confirmed across several readings before any diagnosis. If you see a Crisis result (above 180/120 mmHg) with symptoms such as chest pain or trouble speaking, seek emergency care immediately. Always consult a qualified clinician about your blood pressure.

资料来源

• www.heart.org/en/health-topics/high-blood-pressure/understanding-blood-pressure-readings
• www.ncbi.nlm.nih.gov/books/NBK538226
• my.clevelandclinic.org/health/body/21629-pulse-pressure

由 YouCalc 团队审核 · 最近审核2026年6月4日