Determining which oven thermometer is right for you will depend on the type of oven you use and whether or not you want a thermometer that can give you an instant reading. There are numerous types of oven thermometers with varying features. They range from inexpensive metal thermometers with a dial face that simply displays the temperature to more advanced digital thermometers with many features.
An oven thermometer in its simplest form generally has a metal casing with a dial face. It will either sit on or attach to an oven rack. This type of thermometer reads the temperature of the oven, not its contents. It's mostly used to make sure that the oven is heating properly and that the temperature gauge is reading correctly. For example, if the temperature on the dial of the oven reads 350° F (about 177° c) and the oven thermometer reads 370° F (about 188° C), this may indicate that the oven needs to be calibrated or is not working properly.
If you are searching for an oven thermometer to help determine the temperature of meat or other dishes, you most likely will be looking for a thermometer with a probe. In order to get an accurate internal temperature, the thermometer must be inserted directly into the meat. A basic solution is an instant-read thermometer. These come with either a dial or digital face and are meant to be inserted into a piece of meat for an instant result. Once the probe is inserted, the temperature can be read within seconds to determine if the meat is cooked to the desired temperature.
Although instant-read thermometers come in both digital and dial forms, the digital version could be easier to read but may require that you know the desired temperature. Many dial-face instant thermometers are labeled with the proper temperature for each kind of meat. These can be easier to use if you are not sure what temperature a piece of meat will need to reach to be cooked through. The guides even include variations in degree of cooking from rare to well-done.
For convection cooking or to avoid having to open an oven, there are digital oven thermometers that have a probe that goes into the meat and then a digital face that remains on the outside of the oven. Some are connected with a wire while others are wireless and allow the cook to take them to another location within a specified range. These types of oven thermometers are inserted when the meat is placed in the oven and are not meant to take an instant reading. Rather, the temperature on the gauge rises as the meat cooks. Depending on the specific features of the oven thermometer, many can alert the user when the meat has reached a desired internal temperature.