It is marked to 375 degrees, but I don't trust the markings. When we turn the dial into the unmarked area above 375, it gets there. If we set it at 375, it only rises to about 285 and stays there. I usually drop french fries at about 325-350 based upon testing with a food thermometer. Since I use a therrmometer to determine when the oil is ready, I consider the miscalibration to be a minor issue.