Best In-Ear Thermometers of 2024

You might think a thermometer being easy to clean is mostly a nice bonus, but we found that ease of cleaning actually had a big impact on accuracy in some cases. Infrared thermometers measure temperature based on the detection of infrared light via the sensor in the thermometer’s probe, says Bernie Deitrick, who led our thermometer testing. When you place a probe into an ear, it may come away with earwax stuck to the surface. That earwax can partly block the infrared sensor, meaning the thermometer registers less infrared light—and thus, a lower temperature. We found even small specks of wax could cause noticeable differences in the temperature readings. That’s why ease of cleaning is so important. For a few thermometers, the design of the probe, with tiny ridges around the glass surface, made it difficult to get the glass fully clean.

Thermometers that use a single-use plastic probe cover—which clicks on over the probe—don’t have this problem; they’re very easy to keep clean since all you need to do is toss the used plastic cover. But a majority of the thermometers we tested weren’t made to work with disposable plastic covers. 

If you use the temporal artery feature on the thermometers that offer it, you also don’t need to worry about this, because the thermometers come with a cap that’s placed on the probe to take a forehead reading. It’s just in the case of taking the temperature in the ear without a probe cover that you could run into this problem.

All the thermometers in our ratings earned high marks for accuracy and consistency, so as long as you’re using each of them with a clean probe, you can feel confident about the results. Just read the instructions carefully to make sure you’re using the correct procedure, placement, and cleaning methods. Deitrick recommends practicing with your child at a time when they’re healthy, so you know what to do when it’s the middle of the night and they’re not feeling well. This will also give you a sense of their normal temperature, so you’ll know how far from that they are when they’re running a fever.