Normal body temperature for a healthy adult typically ranges from 97°F to 100.4°F (36.1°C to 38°C). This measurement can vary based on factors such as the time of day, activity level, and individual differences. The average normal body temperature is often cited as 98.6°F (37°C), but it is important to note that this is just a general guideline. Body temperature can be measured using various methods, including oral, rectal, and axillary (underarm) measurements. Each method may yield slightly different results. A temperature above the normal range may indicate a fever, while a lower temperature could suggest hypothermia, both of which require medical attention.