How many degrees Celsius of inaccuracy should a thermometer have?

I have sent an enquiry one week ago about why a digital thermometer seems to have bigger temperature difference, as comparing to the other more accurate thermometer than before.

However one of their support staffs replied as below.

“We have an overall 4 degree tolerance so that is considered accurate.”

I then replied by giving an example of forecast.

“If the forecast says the highest temperature will be 20°C tomorrow but it turns out to be 24°C, then would that be considered as accurate?”

(I did not mention anything about back yard or if the forecast must be very accurate close to where I live.)

Then the staff replied as below.

“If the temperature reading is within 4 degrees of one of our products, or a mercury thermometer, it would be considered accurate. Please keep in mind, your local forecast is not always going to be what the temperature is in your back yard. That could be taken miles from your house. For example, I live a mile away from the air port and my temperature is always about 7-10 degrees different than what they have.”

If that is the case, I am wondering if anyone would want to watch such a forecast that has 7-10 degree difference than where they live.

Please provide some opinions about how many degrees Celsius of inaccuracy should a thermometer have, and also about the example of forecast. Thank you.


Actually I also stated the other example of placing the thermometer in the refrigerator, but the support staff did not respond about that. I will state it below.

If I place the thermometer in the refrigerator and it measures 4°C, but it is actually 4°C less than the actual temperature, then would the foods not become rotten when
the actual temperature is 8°C?”

Default Asked on September 3, 2018 in Science & Technology.
Add Comment
2 Answer(s)

Thank you very much for your inquiry on this very important topics. I think everybody should know about this.

But, is it true?
Have you investigated properly?

You haven’t told us yet that which brands thermometer you are talking about?

Remember, This is a public place. Of course, you should write the correct information. because maybe some affected by your wrong information.


Brong Answered on September 3, 2018.
Add Comment

If the provider provide this tolerance info to you, then I think you should think that this is the correct information.  it is an accurate tool according to the manufacturer.

You may always some error…or potential error… in some types of measurement.

however, precision is much more critical. On the other hand, my oven fluctuates by 25 to 50 degrees F. In the end, you will have to decide if the tolerance is appropriate for your use. That is, how precise of a tool do you actually need? The weather example is not really helpful, as it is more about prediction than measurement.

Thanks for the questions.

Brong Answered on September 4, 2018.
Add Comment

Your Answer

By posting your answer, you agree to the privacy policy and terms of service.