A normal human body temperature is on average 98.6 F (37 C) orally. The normal range can be as low as 97.5 and as high as 98.8 F (36.4 to 37.1 C). The body temperature is considered dangerously low when it's below 95 F (35 C). There are some people with average temperatures in the 96 F range who are fine.
Mild reductions in body temperature are often temporary and don't indicate a serious problem or condition. For example, your temperature normally is lower in the morning than in the evening, when you are inactive as compared to being active.
The most common cause of a lower-than-normal body temperature is exposure to cold. But occasionally, a low body temperature can indicate an underlying problem or condition, such as:
If you have a low body temperature and feel it could be a problem you may want to consult your doctor.
BBT Basal Body Temperature Fertility Charting