Being able to easily read your oven thermometer is critical. Dials with an uncluttered, white background are easier to read. Larger numbers allow you to see temperature readings without opening the oven door and losing heat. The simpler (and larger) the markings, the easier your oven thermometer will be to read. When considering temperature ratings, think about the kinds of foods you like to cook. If you do a lot of baking, consider an oven thermometer that goes up to 500 degrees. Some thermometers provide markings every 10 degrees. While this may be helpful, they can make the dial harder to read.