What is calculated
The AHA category matching one systolic/diastolic reading.
Blood Pressure Category Calculator
Blood pressure reading
Enter your values, then calculate to see a verified result.
Reference range
How this result is calculated
A clear calculation path based on your inputs.
Inputs usedReview the information used for this result.
Full calculation and sourcesOpen Full calculation and sources to review the formula, assumptions, boundaries, and evidence.
Versioned calculationFormula v1.0.1
Method
Apply the higher category reached by either number.
Important boundary
Measurement technique, repeated readings, symptoms, pregnancy, and clinical history matter.
Measure correctlyUse the labeled input and matching unit.
Measured or label valueApply the higher categoryThe calculator applies the stated equation.
Full precision firstFollow the cited actionKeep the boundary beside the result.
Reference, not diagnosisInterpretation
.
Both entered numbers and their difference stay visible.
Do not delay urgent care because of a calculator.
Use this result
Continue with your result
Compare, save, or take the next step
Did we solve your problem?Your feedback helps us improve this calculator.
Report a calculation issue Keep exploring
Related calculators and resources
Method and test recordFormula v1.0.1
- Recorded scope
- health-wellness-completion
- Publisher
- CalculatorGeek
- Recorded review date
- 2026-10-05
- Next source review
- 2027-04-05
- Definition fixtures
- 3 configured scenarios
- Published examples
- 3 shown below
Recorded method
Test every threshold edge, higher-category logic, and visible urgent-care wording.
These records describe the published model and reference tests. A test-case count is not a certification of every possible input or an independent specialist review. Editorial policy
Known limitations
- Applies adult AHA categories, not pediatric or pregnancy-specific criteria.
- Does not validate cuff technique or device accuracy.
- One reading does not diagnose hypertension.
- Does not replace emergency assessment.
Method sources
Latest model update
2026-10-05 - Initial evidence-limited shared-system implementation with fixtures, original support content, and contextual links.
Reference inputs and expected results
Up to 12 examples from the configured definition fixtures are shown. Expected values use the stated output units; invalid inputs are intended to be rejected.
| Case | Inputs | Expected result |
|---|---|---|
| elevated systolic | Systolic pressure: 128 mmHg; Diastolic pressure: 78 mmHg | AHA category index: 2; Pulse-pressure difference: 50 mmHg (allowed numeric tolerance: 0.0001) |
| stage one by diastolic | Systolic pressure: 118 mmHg; Diastolic pressure: 84 mmHg | AHA category index: 3 (allowed numeric tolerance: 0.0001) |
| severe boundary | Systolic pressure: 181 mmHg; Diastolic pressure: 100 mmHg | AHA category index: 5 (allowed numeric tolerance: 0.0001) |
Report an issue with this tool. Include the page URL, units, expected answer, and steps to reproduce. Do not include sensitive personal information.
On this page
What the Blood Pressure Category Calculator calculates
Classify one blood-pressure reading with the current American Heart Association adult category thresholds.
The result uses a visible category label and does not diagnose hypertension from a single reading.
Continue this workflow with the Metabolic Syndrome Criteria Checker. Audit all five NHLBI criteria.
How to use the Blood Pressure Category Calculator
- Use a validated cuff and correct measurement technique.
- Enter systolic and diastolic from the same reading.
- Read the higher category reached by either value.
- Follow current AHA advice for repeated or severe readings.
Continue with the A1C Calculator. Convert A1C into estimated average glucose.
Formula, variables and calculation order
Normal: <120 and <80; elevated: 120-129 and <80; stage 1: 130-139 or 80-89; stage 2: ≥140 or ≥90; severe range: >180 and/or >120.
Inputs are validated and normalized before calculation. Full precision is retained until the displayed result is rounded.
Cross-check a different part of the decision with the Blood Pressure Calculator. Classify a measured systolic and diastolic pair.
Worked example and boundary check
Worked example
128/78 mmHg is classified as elevated by the systolic value.
Boundary check
A reading above 180 and/or above 120 enters the severe range; current AHA instructions distinguish readings with and without symptoms.
How to interpret the result
Use the category as an educational label. Diagnosis and treatment require appropriate repeated measurements and clinical evaluation.
- Applies adult AHA categories, not pediatric or pregnancy-specific criteria.
- Does not validate cuff technique or device accuracy.
- One reading does not diagnose hypertension.
- Does not replace emergency assessment.
For a separate result with different assumptions, open the Cholesterol Ratio Calculator. Calculate common lipid ratios without diagnosing disease.
Frequently asked questions
Which number controls the category?
The higher category reached by either systolic or diastolic.
Is 128/78 normal?
Under the cited AHA categories it is elevated because systolic is 120-129.
Does one high reading mean hypertension?
Not by itself.
What if the reading is over 180/120?
Repeat as directed by the AHA and follow its urgent guidance, especially when symptoms are present.
Primary sources and evidence limits
Sources were checked 2026-10-05. A reference value, conversion, or schedule estimate is not a diagnosis, prescription, individualized treatment target, or substitute for professional care.