Blood pressure comes as two numbers — the pressure when the heart squeezes (systolic, the top figure) and when it relaxes between beats (diastolic, the bottom). For adults, the healthy target is simple and doesn't change with age: below 120/80 mmHg. Where age really matters is in children, whose pressures start low and climb through childhood. Here are the ranges, the categories that define high and low, and why a single cuff reading rarely tells the whole story.
A normal adult blood pressure is below 120/80 mmHg. That's the goal at 25 and at 75 — while average readings drift upward with age, the healthy target doesn't move with it. The American Heart Association sorts readings into these bands:
| Category | Systolic / Diastolic (mmHg) |
|---|---|
| Normal | Below 120 and below 80 |
| Elevated | 120–129 and below 80 |
| Hypertension, Stage 1 | 130–139 or 80–89 |
| Hypertension, Stage 2 | 140 or higher or 90 or higher |
| Hypertensive crisis | Above 180 and/or above 120 — seek care now |
A child's blood pressure is genuinely different from an adult's — it starts low in infancy and builds steadily. Clinically, a child's blood pressure is judged against percentiles for their age, height, and sex, which is more precise than a flat range. The systolic figures below are simplified reference ranges to give you a sense of what's typical at each stage.
| Age | Typical systolic BP (mmHg) |
|---|---|
| Newborn (0–1 mo) | 65–95 |
| Infant (1–12 mo) | 70–100 |
| Toddler (1–3 yr) | 85–105 |
| Preschool (3–5 yr) | 90–110 |
| School-age (6–12 yr) | 95–115 |
| Adolescent (13–18 yr) | 110–130 |
Low blood pressure — hypotension — is generally a reading under 90/60 mmHg. Unlike high pressure, low pressure is only a problem when it produces symptoms: dizziness on standing, light-headedness, blurred vision, or fainting. Plenty of healthy people, especially the young and the fit, simply run low and feel great doing it. The reading that matters is the one that comes with a symptom.
Blood pressure is restless. It rises with stress, a full bladder, a rushed morning, talking during the measurement, or simply the walk into the clinic — the white-coat effect is a real and well-documented bump. A single high number doesn't make a diagnosis; the pattern across several readings, taken calmly and on different days, is what counts.
Technique matters too. Feet flat, back supported, arm resting at heart height, the right cuff size, and a few quiet minutes beforehand all change the result. A cuff that's too small reads falsely high — a classic and easily missed error.
Before treating a single high number as the truth, it's worth knowing how many everyday things nudge blood pressure up for a few minutes at a time. Any of these can inflate a reading without meaning a thing about someone's long-term pressure:
This is why a calm recheck after five quiet minutes so often lands lower than the first startled reading — and why one number on its own is never the full story.
For adults of any age, normal is below 120/80 mmHg — average readings rise with age, but the healthy target doesn't. In children it's lower and increases through childhood, from around 65–95 mmHg systolic in newborns up to roughly 110–130 mmHg by the teens.
Under the current AHA categories, 130/80 mmHg is Stage 1 hypertension — above the normal range of below 120/80. A single reading isn't a diagnosis, though; blood pressure should be confirmed with several readings on different days first.
Low blood pressure (hypotension) is generally below 90/60 mmHg. It's only a concern if it causes dizziness, light-headedness, blurred vision, or fainting. Many healthy people run naturally low and feel completely fine.
A reading above 180/120 mmHg is a hypertensive crisis. With chest pain, breathlessness, severe headache, vision changes, weakness, or difficulty speaking, it needs emergency care immediately. Even without symptoms, that reading warrants an urgent recheck and medical advice.