The four vital signs are body temperature, heart rate (pulse), respiration rate, and blood pressure. These measurements give a quick snapshot of how your body’s most basic functions are performing, and they’re checked at virtually every medical visit, hospital admission, and emergency room triage. Knowing what’s normal for each one helps you understand what your numbers mean and when something might be off.
Body Temperature
Normal body temperature for a healthy adult at rest falls between 97.8°F and 99.1°F (36.5°C to 37.3°C), with 98.6°F (37°C) often cited as the average. A reading above 100.4°F (38°C) is generally considered a fever, typically signaling an infection or illness. Your temperature naturally fluctuates throughout the day, running slightly lower in the morning and peaking in the late afternoon.
Where you take your temperature matters. Ear (tympanic) thermometers tend to be the most accurate consumer option, with readings that deviate less than a tenth of a degree from clinical standards. Forehead and temporal artery thermometers are convenient but can read slightly high, sometimes by nearly half a degree Celsius. Oral digital thermometers fall somewhere in between. If you’re comparing readings from different devices, keep in mind that the numbers won’t match perfectly.
As you age, your baseline temperature doesn’t change much, but your body becomes less efficient at regulating heat. This means older adults may not develop as obvious a fever during an infection, making other vital signs more important for catching illness early.
Heart Rate (Pulse)
A normal resting heart rate for adults is 60 to 100 beats per minute. You can check yours by placing two fingers on the inside of your wrist or the side of your neck, counting beats for 30 seconds, and doubling the number. The best time to measure is first thing in the morning, before caffeine or activity.
Fitness level has a major influence on where you fall in that range. Athletes and people who exercise regularly often have resting heart rates in the 40s or 50s because their hearts pump more blood per beat and don’t need to work as hard at rest. A pulse of 48 in a marathon runner is perfectly healthy, while the same number in a sedentary person could signal a problem.
Children have naturally faster heart rates. Newborns can range from 85 to 205 beats per minute while awake, toddlers from 100 to 190, and school-age kids from 60 to 140. By adolescence, the range settles into the adult norm of 60 to 100. If you’re checking your child’s pulse, don’t compare it to adult numbers.
Respiration Rate
Breathing rate is the vital sign most people never think to check at home, but it can be one of the earliest indicators that something is wrong. The normal range for adults is 12 to 18 breaths per minute. To count it accurately, watch the chest rise and fall for a full 60 seconds while the person is calm and unaware you’re counting (awareness tends to change breathing patterns).
Children breathe faster than adults. Infants take 30 to 60 breaths per minute, toddlers 24 to 40, and school-age children 18 to 30. These rates gradually slow through childhood, reaching adult levels by adolescence.
A rate consistently above the normal range can reflect pain, anxiety, fever, lung problems, or heart conditions. A rate that’s too slow may point to medication effects (particularly sedatives or opioids), neurological issues, or severe fatigue. Because breathing rate responds to so many different problems, a sudden change is worth paying attention to even if the other three vital signs look fine.
Blood Pressure
Blood pressure is recorded as two numbers: the upper number (systolic) measures the force when your heart contracts, and the lower number (diastolic) measures the pressure between beats. A normal reading falls between 90/60 and 120/80 mmHg. Readings of 120 to 129 systolic with a diastolic under 80 are considered elevated, and anything at 130/80 or above enters the range of high blood pressure.
A reading of 180/120 or higher is a medical emergency, especially if accompanied by chest pain, shortness of breath, numbness, weakness, vision changes, or difficulty speaking.
Getting an accurate blood pressure reading requires more care than most people realize. A Johns Hopkins study found that common arm positions can substantially overestimate results. For the most reliable reading, sit with your back supported and feet flat on the floor, rest your arm on a desk or table so the cuff sits at mid-heart level, and stay quiet for five minutes before measuring. Don’t cross your legs, talk, or look at your phone during the reading. Empty your bladder beforehand, as a full bladder can raise your numbers. The cuff size also matters: one that’s too small will give falsely high readings.
Blood pressure tends to creep upward with age, and the risk of hypertension increases significantly after 65. Older adults are also more prone to orthostatic hypotension, a sudden drop in blood pressure when standing up that can cause dizziness or lightheadedness.
The “Fifth Vital Sign”
You may hear pain referred to as the fifth vital sign. The American Pain Society originally promoted this phrase to encourage healthcare providers to routinely screen for pain the same way they check the other four measurements. The Veterans Health Administration adopted this approach system-wide, asking patients to rate their pain on a 0 to 10 scale and recording the score alongside traditional vital signs.
Oxygen saturation, measured with a small clip-on device called a pulse oximeter, is another metric that’s increasingly treated as a core measurement in hospitals and clinics. Neither pain nor oxygen saturation has officially replaced the traditional four, but both are now recorded so routinely that the line between “standard” and “additional” vital signs continues to blur.
Normal Ranges at a Glance
- Body temperature: 97.8°F to 99.1°F (36.5°C to 37.3°C)
- Heart rate: 60 to 100 beats per minute
- Respiration rate: 12 to 18 breaths per minute
- Blood pressure: 90/60 to 120/80 mmHg
These ranges apply to healthy adults at rest. Children, athletes, older adults, and people on certain medications may have baselines that fall outside these numbers without anything being wrong. What matters most is knowing your own baseline and noticing when something shifts.