Are Food Thermometers Accurate? You Need to Know This

Food thermometers are used to measure and check out a food’s internal temperature. Basically, food thermometers are accurate as they operate like any other typical thermometer. Through contact with the necessary area, they sense the temperature and display it to users. 

In various ways, food thermometers have become an important addition to our kitchen. They save time and even reduce the stress of second-guessing if cooked meals are ready. They make following cooking guides easy, even for a beginner.

Although food thermometers are becoming a thing, many are still skeptical about how accurate they are. So, it’s okay you’re asking the question of how accurate they are. You’re not alone.

I will be guiding you on how to test food thermometer accuracy, how to use it properly, and everything else you need to know about food thermometer accuracy.

SEE: A Simple Food Thermometer Guide for Those Who Take Food Safety Seriously

Is a Food Thermometer Accurate?

Yes, it is. A food thermometer will accurately provide the temperature for your prepared meal. Placed in the right spots of food, the thermometer reads the internal temperature of your meal. Nonetheless, the best way to find out food thermometer accuracy is by testing it.

Talking about how accurate a food thermometer is will also eventually bring us to how accurate all thermometers are. Moreover, if you trust that your human thermometer is accurate, then you have no reason to doubt the food thermometer. This is because they are built in the same way or created to function alike.

The only difference being food thermometers are created to work specifically with food and are made to be inserted into our food’s thickest parts. 

How to Check a Food Thermometer’s Accuracy

There are two methods to prove that food thermometers are accurate. They are the ice water technique and the boiling water technique.

The ice water technique

Universally, it is generally accepted that the freezing point of water is 0°C or 32°F. With the ice water technique, all we have to do is get ice water and let our thermometer do the measuring.

How it works

Get a glass of ice and distilled water. Fill the glass(containing ice) with water and stir well until the water assumes another temperature. Insert your food thermometer into the water, and wait for about 20-30 Seconds.

Do not allow the thermometer to touch the bottom of the glass of ice or the sides. However, dip the thermometer enough such that the thermometer stem is submerged. An accurate food thermometer will give you 0°C or 32°F because that is expected to be the temperature of the water at that moment.

The boiling water technique

This complements the ice water technique of determining a food thermometer’s accuracy. Already we know that 100°C or 212°F is the accepted boiling point of water. We will use this to also check if our thermometer works correctly.

How it works

Bring water to a rolling boil (preferably in a pot). Insert your thermometer into it. Like the ice water technique, do not allow the thermometer to touch the bottom of the glass of ice or the sides. Wait for a few seconds as well- 20-30 seconds. Then take the readings. Also, if your thermometer is accurate, it is expected to read 100°C or 212°F.

SEE: Are Food Thermometers Safe? You Need to See This

How Do You Calibrate a Food Thermometer

To calibrate a thermometer means to adjust your thermometer so that it takes readings like a standardized thermometer. Did your food thermometer fail the ice water test? Or rather it failed the boiling water test? Here’s what to do:

To calibrate a digital thermometer

Not all digital thermometers can be calibrated. On some of them, you simply need to press the reset button. You can check the manufacturer’s guide to know if your thermometer can be calibrated or not. 

For others that can be calibrated, adjust the nut/screw by turning. Then do this until the accurate reading is reached. While tuning the nut/screw, ensure the thermometer is still placed in the water, do not remove it.

To calibrate a non-digital thermometer

Dial thermometers often have a calibration nut under the head. You’ll find it in a hexagonal shape. Turn the nut slightly to adjust the thermometer to the required temperature. You should also do this when the thermometer is in boiling water or ice water.

To calibrate mercury or liquid-in-glass-tube thermometer

This type of thermometer cannot be calibrated using DIY techniques. The only way around it is to return to the manufacturer for correction.

Why Should You Calibrate Your Thermometer?

  • Calibrate your thermometer when you notice it doesn’t give accurate readings. Calibration will help to adjust it
  • Calibrate your thermometer after using it to take readings of very high temperature
  • When you get a new food thermometer, you should calibrate it 
  • Whenever you drop your thermometer, it is advised that you calibrate, as it might have been affected.
  • Occasionally, you should also calibrate your thermometer. If you use it regularly, you should calibrate it weekly.

After calibrating your thermometer, it is advised that you test it to ensure that it’s working properly. You can test it using either the ice water technique or the boiling water technique.

Factors That Affect a Food Thermometer’s Accuracy

Sometimes when your thermometer is not accurate, here are things to watch out for


When using your food thermometer do not insert it too deep into the food. A maximum depth of 2 inches is the ideal depth. Also, do not position it in a place too shallow. Shallow positioning takes the temperature of the external part of the food rather than the inner.

Additionally, do not position your thermometer where there are fats or bones. They hinder the thermometer from working effectively.

SEE: How to Use a Food Thermometer

Measurement error

Are you using the right thermometer for the right type of food? Various food types require thermometers effective and active enough to stand their layers and take an accurate temperature.

The use of the wrong type may lead to inadequate measurement. Instant-read thermometers are good for poultry products and all types of meat, soup, and sauce.

The deep-fry works for oil and sugar. The Thermometer-fork combination is best used when grilling. Oven-proof works accurately in casseroles, roasts, and soups. Understand this as it will help you when picking a thermometer.

Human error

Before judging your thermometer for being inaccurate, how well can you use one? Sometimes inaccuracy on the part of the thermometer may be caused by human error.

Did you place your thermometer at the right time? Did you place it well? Can you take the reading accurately? And did you place it in for the right amount of time?

While some thermometers require that you place them in for about 10 seconds, others may require more or less. Understand and know how to use the type of thermometers you have.

An oven thermometer can be left in for a long time while an instant-read thermometer cannot.

Thermometer sensor

At some other time, the issue can be found in your thermometer’s sensor. Therefore, if there’s been a sensor error from the thermometer, your readings will not be accurate.

SEE: Enjoy a Good Off Price at Moe’s Southwest Grill


Are digital food thermometers accurate?

Yes, they are. Digital food thermometers are quite accurate unless affected by one or two factors. They are some of the easiest food thermometers to use and they take accurate measurements.

How often must food thermometers be calibrated?

If used regularly, a food thermometer should be calibrated often. It’s required you test regularly as well so that you can catch any irregularities if any were to occur. Test and calibrate your thermometer to keep it working accurately.

How often should you use a food thermometer?

As often as you want. As long as you want to know the inner temperature of your food, you should use the food thermometer. There are no cons to using it. As long as it’s available to use, you might as well pop it into your cooking to guide you.

Can a food thermometer cause your food to spoil?

No, it cannot. A food thermometer is harmless both to you and your meals. They do not cause damages of any type. You simply have to ensure you place it correctly so that it doesn’t cause unpleasant holes in your meals.

What is the proper way to take food temperature?

Insert the thermometer into the thickest part of the food. This way you have a feel of the innermost part of the meal. For liquids, however, there are no thick parts which are why you should insert your thermometer in after stirring.

Are accurate food thermometers expensive?

No, they are not. However, all thermometers do not sell for the same price. You’ll find out that digital thermometers cost a lot more than instant-read types.

The oven dial thermometers also have a different price from the thermometer-fork combination. Nonetheless, you will definitely find one that suits your budget anytime. 

What is an important factor to consider when choosing a food thermometer?

Accuracy and use. An accurate thermometer is a good thermometer, therefore always pick that over other ones anytime.

Also, what you intend to use your thermometer for is an important factor that should influence your decision when buying. Food thermometers have their food preferences. Based on the food you plan to cook, choose a thermometer that works.


Food thermometers are of various types, and their accuracy depends largely on how well you can utilize, test, calibrate and maintain them. Food thermometers are accurate. When you’re not sure that your thermometer is working well, testing it using the methods above is the way to go.

Therefore, always test the accuracy once in a while. Furthermore, clean and care for it properly. And if your food thermometer is not working properly, check for possible errors. If it needs fixing, fix it. Whereas, if it is beyond repair, replace it.

Thanks for reading.

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