What is the normal resting respiratory rate for an adult?

• A. 8-12 breaths per minute
• B. 24-30 breaths per minute
• C. 12-20 breaths per minute
• D. 30-40 breaths per minute

Answer: (C)

Normal resting breathing for an adult is about 12 to 20 breaths per minute. This rate keeps oxygen and carbon dioxide balanced while at rest. Breathing noticeably slower than that at rest is bradypnea and can occur with sleep, certain medications, or some medical conditions. Breathing noticeably faster than that is tachypnea and can signal fever, infection, anxiety, or respiratory or metabolic problems. Among the options, 12-20 fits the standard resting range for adults, while 8-12 is typically too slow for resting, and 24-30 or 30-40 are clearly rapid and not normal at rest. When assessing, count for a full minute to get an accurate rate and note whether breaths are shallow or labored.