The ideal temperature for the freezer is about 5 degrees (F). The refrigerator should be kept at about 36 degrees (F). The temperature can be adjusted using the controls found inside the freezer or refrigerator.
Measurement of the temperature in the freezer may be inaccurate if you simply place a thermometer inside. To properly Measure the temperature, place a cup of alcohol or cooking oil with a cooking thermometer into the freezer for about 2 hours. The oil or alcohol will not freeze and will make it possible to accurately measure the temperature. If you used water, it would freeze and the thermometer would not display the correct reading. Also, the freezing water may damage a thermometer placed in it.