Blood Pressure Category Calculator
Where a reading falls under the 2017 ACC/AHA guideline — the one that moved the hypertension line down to 130/80 and deleted "prehypertension". It also tells you which of your two numbers put you there, which is the part that changes what you'd do about it.
Category
Reading
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Driven by
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Systolic alone
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Diastolic alone
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Pulse pressure
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Mean arterial pressure
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Next category at
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The categories
| Category | Systolic | Diastolic | |
|---|---|---|---|
| Normal | under 120 | and | under 80 |
| Elevated | 120–129 | and | under 80 |
| Stage 1 | 130–139 | or | 80–89 |
| Stage 2 | 140 or higher | or | 90 or higher |
| Crisis | over 180 | and/or | over 120 |
Source: Whelton et al., 2017 ACC/AHA guideline, Hypertension 2018;71:e13–e115.
The and/or is the whole thing
Notice that "Normal" and "Elevated" use and, while stages 1 and 2 use or. That asymmetry catches people out. A reading of 125/85 looks like it should be "Elevated" because the top number is in the 120–129 band — but Elevated requires the bottom number to still be under 80, and 85 isn't. So 125/85 is stage 1 hypertension, driven entirely by the diastolic.
The other half of the rule: when the two numbers land in different categories, the higher one wins. 150/85 is stage 2, even though the diastolic alone would only be stage 1. This calculator shows both numbers' categories separately so you can see which one is actually the problem.
Why the line moved to 130/80
Before 2017, hypertension started at 140/90 and 130–139/80–89 was called "prehypertension". The guideline reclassified that band as stage 1 because the outcome data showed real, accumulating cardiovascular risk within it — roughly double the risk of a normal reading. The change didn't put most of those people on medication: for stage 1 without high overall cardiovascular risk, the recommendation is lifestyle change and a recheck in 3–6 months. What it did was stop calling that range "pre"-anything.
A single reading is not a diagnosis
Hypertension is diagnosed from an average of two or more readings taken on two or more separate occasions, measured properly. Blood pressure swings 10–20 mmHg through a normal day. Getting it right means: seated five minutes, back supported, feet flat, arm at heart height, correct cuff size, no caffeine or exercise in the preceding 30 minutes, and no talking during the measurement. Talking alone adds around 10 mmHg. So does a cuff over a sleeve, and so does a full bladder.
White-coat hypertension — high in the clinic, normal at home — is common enough that home or 24-hour ambulatory monitoring is now the preferred way to confirm a diagnosis.
Pulse pressure, the third number
The gap between the two readings. Typically around 40 mmHg. Consistently above 60 suggests stiffened arteries and is an independent risk marker in adults over 50 — it's why an older person's 160/70 is more concerning than the diastolic alone suggests. Under about 25 can indicate the heart isn't ejecting well. This is context, not a diagnosis.
FAQ
My reading says hypertensive crisis. What now?
Sit quietly for five minutes and measure again — a single very high reading is often measurement error or a transient spike. If it stays above 180/120, that needs medical attention promptly. If it comes with chest pain, shortness of breath, back pain, weakness or numbness, vision change, or trouble speaking, that's an emergency: call emergency services rather than driving yourself.
Which number matters more?
Systolic, for most adults over 50 — it keeps rising with age as arteries stiffen and it predicts cardiovascular events better in that group. Under 50, diastolic carries relatively more weight. Both are in the guideline because both matter; isolated systolic hypertension is the most common pattern in older adults.
What lowers blood pressure without medication?
The evidence-backed levers, roughly in order of effect: weight loss (about 1 mmHg per kilogram lost), the DASH eating pattern (8–14 mmHg), cutting sodium (2–8 mmHg), regular aerobic exercise (4–9 mmHg), and limiting alcohol (2–4 mmHg). They stack. For many people in stage 1 that's genuinely enough to get back under the line.
Are home monitors accurate?
Validated upper-arm cuffs are good; wrist and finger monitors are considerably less reliable because position affects them so much. Check your device against a clinic reading once, and take two or three readings a minute apart each time, discarding the first — it's usually the highest.
Is this medical advice?
No. It classifies one reading against a published table. It cannot diagnose hypertension, doesn't know your cardiovascular risk, medications, or history, and shouldn't be used to start, stop, or change any treatment. That's a conversation with a doctor.
Estimate — not medical advice
A single reading is not a diagnosis. Hypertension is diagnosed from an average of readings taken on separate occasions, measured properly. If a reading is above 180/120, re-measure after resting — and if it stays there, seek medical care promptly.
This is an estimate, not medical advice, and not a diagnosis. It doesn't know your history, your medications, or your other results, and it should never be used to start, stop, or change treatment. If a number here concerns you, take it to a doctor or pharmacist rather than acting on it.