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Blood pressure category calculator

Blood pressure category (AHA/ACC) for a systolic/diastolic reading, from normal to stage 2 and severe hypertension, with pulse pressure and MAP.

Drafted with AI writing toolsUpdated Checked examples: 7

mmHg
mmHg
Try
Category (AHA/ACC)
Normal
Category (AHA/ACC): Normal
Systolic alone
Normal
Diastolic alone
Normal
Pulse pressure
42mmHg
Mean arterial pressure
90.0mmHg
A category needs the average of two or more readings taken on two or more occasions; one reading can't diagnose hypertension.

118/76 mmHg is “Normal” under the AHA/ACC categories (2017, kept in 2025), set by both numbers.

Systolic

NormalStage 1Stage 2Severe90120130140180200118 mmHg

Diastolic

NormalStage 1Stage 2Severe50809012013076 mmHg
How it's calculated S

  1. Classify the systolic number

    SBP=118 mmHg\text{SBP} = 118\ \text{mmHg}

    Normal

    Normal < 120, elevated 120–129, stage 1 130–139, stage 2 ≥ 140, severe > 180.

  2. Classify the diastolic number

    DBP=76 mmHg\text{DBP} = 76\ \text{mmHg}

    Normal

    Normal < 80, stage 1 80–89, stage 2 ≥ 90, severe > 120.

  3. Take the higher category

    The AHA/ACC guideline places a reading that falls in two categories in the higher one: Normal.

  4. Pulse pressure and mean arterial pressure

    PP=118−76=42,MAP≈76+423=90.0 mmHg\text{PP} = 118 - 76 = 42,\qquad \text{MAP} \approx 76 + \frac{42}{3} = 90.0\ \text{mmHg}

About the blood pressure category calculator

A reading is placed in the AHA/ACC adult categories, set in 2017 and kept unchanged by the 2025 guideline: normal is below 120/80 mmHg, elevated is 120–129 systolic with diastolic below 80, stage 1 hypertension is 130–139 or 80–89, and stage 2 is 140 or higher or 90 or higher. When the two numbers fall in different categories, the higher one applies. Pulse pressure (systolic minus diastolic) and mean arterial pressure (diastolic plus a third of the pulse pressure) are shown too.

People use it to read a home or clinic measurement. The default 118/76 mmHg is normal, with a pulse pressure of 42 and a mean arterial pressure of 90 mmHg; 130/80 would already count as stage 1 hypertension.

The categories describe average blood pressure from repeated, properly taken readings, so one reading cannot diagnose hypertension. Above 180 systolic or 120 diastolic the 2025 guideline calls it severe hypertension, and a hypertensive emergency when there are signs of acute organ damage.

What blood pressure category is my reading?

Adult readings use the AHA/ACC categories, kept unchanged by the 2025 guideline: normal is below 120/80 mmHg, elevated is 120–129 systolic with diastolic below 80, stage 1 is 130–139 or 80–89, and stage 2 is 140 or more, or 90 or more. The higher category applies, so 128/92 is stage 2.

The categories describe the average of two or more readings taken on two or more occasions. One reading cannot diagnose hypertension.

Blood pressure chart for adults

The thresholds from the 2017 ACC/AHA guideline, Table 6, which the 2025 AHA/ACC guideline kept:

  • Normal: systolic below 120 and diastolic below 80
  • Elevated: systolic 120–129 and diastolic below 80
  • Stage 1 hypertension: systolic 130–139 or diastolic 80–89
  • Stage 2 hypertension: systolic 140 or higher, or diastolic 90 or higher
  • Severe hypertension: systolic above 180 and/or diastolic above 120

Diastolic pressure has no elevated band, so a diastolic of 80 is already stage 1.

Why the higher number decides

Each number is classified on its own and the reading takes the higher of the two categories:

  • 118/76: both normal, so normal.
  • 125/79: systolic elevated, diastolic normal, so elevated.
  • 120/80: systolic elevated, diastolic stage 1, so stage 1.
  • 138/76: systolic stage 1, diastolic normal, so stage 1.
  • 140/79: systolic stage 2 on its own, so stage 2.
  • 128/92: diastolic stage 2, so stage 2 despite an elevated systolic.

When blood pressure is dangerously high

Above 180 systolic and/or 120 diastolic, the 2025 guideline calls the reading severe hypertension. With signs of acute organ damage it becomes a hypertensive emergency, which needs monitored hospital treatment.

If a reading is that high and you have chest pain, shortness of breath, weakness, or changes in vision or speech, call emergency services (AHA). Without symptoms, a reading above 180/120 still needs prompt medical attention.

Both limits are strictly greater than, so 180/120 itself is stage 2 and 180/121 is severe. That boundary is a classification detail; it does not make 180/120 a safe reading.

Low blood pressure

The hypertension categories have no low band, so a low reading such as 85/65 shows as normal. The NHS usually calls a reading below 90/60 mmHg low blood pressure; if you feel dizzy or faint, see a clinician (NHS).

Pulse pressure and mean arterial pressure

Pulse pressure is systolic minus diastolic. Mean arterial pressure (MAP), the average pressure over one heartbeat, is commonly estimated as diastolic plus a third of the pulse pressure, the same as (systolic + 2 × diastolic) ÷ 3.

For 118/76, pulse pressure is 118 − 76 = 42 mmHg and MAP is 76 + 42 ÷ 3 = 90 mmHg.

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. Neither number changes the category.

Three worked cases

  • Default: 118/76 mmHg.
  • Diastolic decides: 120/80 mmHg.
  • Exact severe boundary: 180/120 mmHg.
ScenarioCategory comparisonPulse pressure (mmHg)Estimated MAP (mmHg)
DefaultNormal4290.0
Diastolic decidesStage 1 hypertension4093.3
Exact severe boundaryStage 2 hypertension60140.0

How to measure blood pressure for a reliable category

The 2025 guideline bases diagnosis on averaged readings taken under standard conditions:

  1. Use a validated upper-arm monitor with a cuff of the right size.
  2. Rest quietly for a few minutes first.
  3. Sit with your back and arm supported and the arm at heart level, and don't talk.
  4. Take readings on several days and average them.

The categories are for adults. Pregnancy and children have their own criteria, which a clinician applies.

The heart-rate zone calculator sets exercise intensities from heart rate. For body-size screening, see the BMI calculator and the waist-to-hip ratio calculator.

Worked examples

118/76

Systolic (top number)
118 mmHg
Diastolic (bottom number)
76 mmHg
Category (AHA/ACC)
Normal
Pulse pressure
42 mmHg
Mean arterial pressure
90.0 mmHg

Checked against: ACC/AHA 2017 Table 6: <120 and <80 is normal; MAP 76 + 42/3 = 90

Boundary 130/80

Systolic (top number)
130 mmHg
Diastolic (bottom number)
80 mmHg
Category (AHA/ACC)
Stage 1 hypertension
Systolic alone
Stage 1 hypertension
Diastolic alone
Stage 1 hypertension
Mean arterial pressure
96.7 mmHg

Checked against: ACC/AHA 2017 Table 6: 130–139 or 80–89 is stage 1; MAP 80 + 50/3 = 96.67

Boundary 120/80 takes the diastolic category

Systolic (top number)
120 mmHg
Diastolic (bottom number)
80 mmHg
Category (AHA/ACC)
Stage 1 hypertension
Systolic alone
Elevated

Checked against: ACC/AHA 2017 Table 6: SBP 120 is elevated, DBP 80 is stage 1; readings in two categories take the higher one

128/92

Systolic (top number)
128 mmHg
Diastolic (bottom number)
92 mmHg
Category (AHA/ACC)
Stage 2 hypertension
Systolic alone
Elevated
Diastolic alone
Stage 2 hypertension

Checked against: ACC/AHA 2017 Table 6: DBP ≥ 90 is stage 2, which outranks elevated SBP

Questions

What is a normal blood pressure?

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.

What blood pressure is stage 1 and stage 2 hypertension?

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.

What blood pressure is dangerously high?

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.

What are pulse pressure and mean arterial pressure?

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.

How should blood pressure be measured?

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.

About this calculator

category=max⁡(cat(SBP), cat(DBP)),MAP≈DBP+13(SBP−DBP)\text{category} = \max\big(\text{cat}(\text{SBP}),\ \text{cat}(\text{DBP})\big),\qquad \text{MAP} \approx \text{DBP} + \tfrac{1}{3}(\text{SBP} - \text{DBP})

Sources

  1. 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
  2. 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
  3. NHS — Low blood pressure (hypotension): below 90/60 mmHg

For information only, not medical advice. These formulas describe populations, not you; talk to a clinician before acting on a result.

Checked against references

This calculator includes 7 worked examples with independently sourced answers. They run in the test suite, and you can run them here too.

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