An instant-read thermometer is a must-have tool for checking temperatures and gauging the doneness of all sorts of things. Because you rely on your thermometer for accuracy, it’s a good idea to check its calibration occasionally and adjust it as need be. To check the calibration, bring a small pan of water to a rolling boil and take the water’s temperature; it should be 212ºF or a few degrees less, depending on your altitude and air pressure. (For the boiling point in your location, visitwww.virtualweberbullet.com.) If the calibration is off, you can adjust a standard (analog) thermometer by turning the hex nut under the thermometer’s face with pliers. If the nut resists, use a second set of pliers to grip the sides of the face and turn the tools in opposite directions. There are only a few models of digital thermometers that can be adjusted. Some calibrate automatically, and others need manual adjustment; follow the manufacturer’s instructions for your model.