How can you tell if your food thermometer is calibrated?

Testing a food thermometer in ice water or boiling water is a reliable method to ensure it is calibrated accurately. When using ice water, a properly calibrated thermometer should read 32°F (0°C) since that is the freezing point of water. Testing in boiling water should yield a reading of 212°F (100°C) at sea level, allowing you to assess the thermometer's accuracy at both ends of the temperature spectrum.

This method provides a practical and straightforward means of verification that is essential for safe food handling—ensuring that food is cooked to the correct temperatures to prevent foodborne illnesses. Other methods, such as checking color or shaking the thermometer, do not provide a meaningful assessment of its accuracy, and relying solely on the instruction manual may not account for the specific environmental conditions or the user's operational understanding of the thermometer.