The U.S. Food and Drug Administration (FDA) says the proper temperature is no warmer than 41 degrees. The agency recommends you use a thermometer inside the refrigerator and adjust the controls if it is too warm.
The agency also says don't let foods sit out too long after cooking. While it may seem like a good idea to let a hot dish cool for hours, the FDA says you need to refrigerate food after no more than two hours.