Vital signs are the fastest honest read you get on a patient — five quick numbers that, taken together, often say more than a page of history. The catch is that "normal" isn't a single figure. It shifts with age, and a heart rate that's perfect for a newborn would have you reaching for the call bell in a grown adult. Below are the ranges nurses actually work from at the bedside, for adults and for children, plus the context that stops one stray number from telling the wrong story.
| Vital sign | Normal adult range (at rest) |
|---|---|
| Heart rate (pulse) | 60–100 beats per minute |
| Respiratory rate | 12–20 breaths per minute |
| Blood pressure | Below 120/80 mmHg |
| Temperature | 36.1–37.2°C (97–99°F) |
| Oxygen saturation (SpO₂) | 95–100% |
Those are resting ranges for a healthy adult, and resting is the operative word. Take a pulse the moment someone's walked in from the car park and it'll read high — that's not tachycardia, that's the stairs. The numbers only mean something once the person has settled.
Sixty to a hundred is the standard band, but fitness bends it. Endurance athletes often sit in the low 50s, sometimes the 40s, and feel completely fine — a well-conditioned heart simply moves more blood with each beat. Push the other way and a fast pulse usually has a reason behind it: fever, pain, blood loss, dehydration, anxiety, too much caffeine. The useful question is rarely just "what's the number" but "what would explain it."
The American Heart Association puts normal at anything under 120/80 mmHg. Above that, it climbs through a few tiers:
| 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 |
One high reading doesn't make a diagnosis. Blood pressure swings with stress, a full bladder, a rushed morning, even the walk down the corridor — the white-coat bump is real. It's the pattern across several readings that counts, not a single cuff.
Twelve to twenty breaths a minute for an adult. It sounds trivial, and it's the vital that gets fudged the most — people glance for a few seconds and multiply, or skip it altogether. Don't. A quietly rising respiratory rate is often the very first sign a patient is heading downhill, sometimes hours before the blood pressure moves. When something feels off, count a full minute.
A healthy adult runs around 37°C (98.6°F), give or take — roughly 36.1 to 37.2°C (97 to 99°F) is ordinary. It drifts across the day, lowest in the small hours and highest in the late afternoon, and the site you measure (oral, tympanic, axillary, rectal) nudges it too. Fever begins at 38°C (100.4°F). If you're weighing up a specific reading, the fever chart on our temperature converter breaks it down degree by degree.
A pulse oximeter reading of 95 to 100% is normal for most people breathing room air, and below 90% is a genuine concern worth acting on. Two honest caveats: patients with long-standing COPD sometimes live comfortably in the upper 80s, so their baseline isn't the textbook's; and the probe lies when fingers are cold, nails are painted, or circulation is poor. If the number looks alarming but the patient looks fine, check the probe before you panic.
Children aren't small adults — their numbers run on a different scale, and the younger they are, the further from adult ranges they sit. Little hearts beat fast and little lungs breathe fast, while blood pressure starts low and creeps up through childhood. The one thing that doesn't change with age is temperature: a fever is still 38°C (100.4°F), newborn to teenager.
| Age | Heart rate (bpm) | Respiratory rate | Systolic BP (mmHg) |
|---|---|---|---|
| Newborn (0–1 mo) | 100–160 | 30–60 | 65–95 |
| Infant (1–12 mo) | 90–150 | 30–50 | 70–100 |
| Toddler (1–3 yr) | 80–130 | 24–40 | 85–105 |
| Preschool (3–5 yr) | 75–120 | 22–34 | 90–110 |
| School-age (6–12 yr) | 65–110 | 18–28 | 95–115 |
| Adolescent (13–18 yr) | 60–100 | 12–20 | 110–130 |
These are PALS-based reference ranges; you'll see slight differences between textbooks, and that's normal — treat them as guide rails, not hard lines. The pattern worth committing to memory: in a sick child, heart rate and respiratory rate climb first. Kids compensate beautifully and can hold a normal blood pressure until they're genuinely unwell, so a reassuring BP never rules trouble out on its own. By the time a child's pressure finally drops, they've usually been working hard to prop it up for a while.
A number outside the range isn't an emergency on its own — context and trend decide that. Someone can be pale, clammy, and confused with "normal" vitals, or sitting comfortably with numbers that look off on paper. Read the whole patient, not one figure. That said, some situations call for prompt medical attention rather than watchful waiting:
When in doubt, get a clinician's eyes on the patient. That's not being over-cautious — that's the job.
The five standard vital signs are heart rate (pulse), blood pressure, respiratory rate, body temperature, and oxygen saturation (SpO₂). Pain is often recorded alongside them, sometimes called the fifth or sixth vital sign.
It can be. A resting pulse of 55 sits below the usual adult range of 60 to 100, but it's common and healthy in physically fit people and during sleep, because a well-conditioned heart pumps more blood per beat. A slow pulse only needs review if it comes with dizziness, fainting, breathlessness, or fatigue.
For adults, normal is below 120/80 mmHg regardless of age. In children it's lower and rises through childhood — from roughly a systolic of 65–95 mmHg in newborns up to about 110–130 mmHg by the teenage years. See the pediatric chart above for age-by-age ranges.
No. 37.5°C (99.5°F) is a low-grade or borderline temperature — just above normal but below the 38°C (100.4°F) fever threshold. It can be an early sign of illness, so recheck it and watch for other symptoms.
For most people, an SpO₂ of 95 to 100% is normal and below 90% is a concern worth attention. People with chronic lung disease such as COPD may have a lower normal baseline, and a cold finger, nail polish, or poor circulation can make the probe read falsely low.