Thermoworks just announced their newest product, the Thermapen ONE this week. We've been huge fans of the Mk4 for quite some time, so we were particularly excited to learn how they improved on this great product.

And since we were so curious how the two generations of Thermapens compared, we decided our followers might be as well.

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Thermapen ONE vs. Thermapen Mk4

While the ONE is very similar to its predecessor, there are several features that definitely set it apart.

Thermapen ONE

Thermapen Mk4

thermapen one
Thermapen Mk4

Auto-rotating display

Auto-rotating display

Waterproof to IP67

Waterproof to IP67

Motion-sensing sleep and wake mode

Motion-sensing sleep and wake mode

Readings within 1 second 

Readings within 2-3 seconds

±0.5°F accuracy

±0.7°F accuracy

5 year warranty

2 year warranty

Brighter and more-responsive automatic backlight

Intelligent backlight

10 color options

Limited color options left

easier access to the user settings


What We Loved About the Thermapen ONE

Auto-Rotating Display

This particular feature appears to function in exactly the same way as in the Mk4. I absolutely love that no matter what way I'm holding it, the display is easy for me to read without craning my neck. If for some reason you don't appreciate this feature as much as I do, you can change the settings to lock the display in your preferred orientation.

360° rotating display
360° rotating display
360° rotating display
360° rotating display

Intelligent Backlight

In this new version of the Thermapen, the backlight is even brighter than the Mk4 and is slightly more responsive as well. Since I'm usually grilling in the dark through most of the winter, I absolutely love this feature on my instant read thermometer.

backlight comparison of Thermapen ONE and Mk4

User Settings Access

I'll be honest, I don't require access to the user settings often. But I like to know I can get to them easily should I suddenly feel the need to measure temperature to the tenth of a degree. The user settings and battery compartment on the ONE are way easier to access than the Mk4.

Battery compartment of Thermapen One

5 Year Warranty

Nothing says a company stands behind their product more than extending the life of their warranty. This speaks volumes to the quality that Thermoworks puts into this product.

Final Thoughts on the Thermapen ONE

instant read thermometer ice water test

I didn’t think the Thermapen could get any better but they actually managed to achieve it! I wouldn't say there were any mind-blowing changes; it is still very similar to the Mk4. However, it is clearly the more advanced version of this instant read thermometer.

So which Thermapen should you buy?

Well, the Mk4 won't be around much longer; particularly at the current closeout price of $69. That's a real steal and anyone who doesn't already have an instant read thermometer should definitely snag that as long as they still can.

That being said, the Thermoworks Thermapen ONE is honestly the best instant read thermometer we've tested to date. So if you like to have the best of the best, look no further and order ONE for yourself.