The sun is out and will mean its BBQ time so a better way to make sure your steak is cooked to perfection is with the use of a food thermometer. As there is nothing worse than undercooked chicken or an overcooked steak. 


In this review, we got the chance to test the Thermapen One which is the updated version of the previous Thermapen MK4 which is a digital thermometer ideal for this year’s BBQ but can also be used indoors when you’re cooking a Sunday roast or the dreaded Christmas roast or just baking a cake.


Who is Thermapen? 

The Thermapen ONE is manufactured by ETI in the UK and sold under ETI’s own name and via the website The UK award winning manufacture started back in 1983 when husband and wife Peter & Miriam Webb saw a gap in the market. The Thermapen is used throughout the food industry and this company remains in family ownership. 


You may have seen the Thermapen used by celebrity chefs as it provides accurate readings and it is very convenient to use as it eliminates the need to guess when your food is done.  


The Thermapen One – Design


The Thermapen One currently costs £66 and is available in 10 different colours which is an improvement from the original. 

Design-wise it is very much the same design as the previous model the MK4. It has that same plastic build that uses biomaster antimicrobial technology which is used to reduce bacterial growth. It comes with a small LCD display on one side which comes with an auto intelligent cool white backlit display. The Display will show you the temperature in either Celsius or Fahrenheit with the size of the display 14.3mm x 11.85mm (Horizontal x Vertical). The overall size of the Thermapen One is 48.2mm x 156.2mm x 19.3mm and is very lightweight at 115 grams.  The Thermapen One also has a temperature range of -49.9°C to 299.9°C. Accurate to 3°C (-19.9 to 119.9°C) or 4°C (-49.9 to 199.9°C)   



The metal probe folds out for you to test that the food is at the right temperature.  If you compare them both you might mistake them for the same product. The Thermapen One has had very subtle differences in the design for example the access to the battery compartment has now improved. The Thermapen One uses a 1x AAA battery that will give 2000 hours of use. 


Apart from that, both models have an auto-rotating display that indicates the temperature and both have a motion sensor sleep and wake mode. Finally, both are IP67 rated meaning it’s waterproof.  


As you can see the Thermapen One vs Mk4 has an identical design.  Image

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The Thermapen One – Unboxing


Inside the packaging, you get the Thermapen One, Quick Start Guide and a detailed instruction manual. Which I have to say is worth reading to get a full understanding of how it works. You also get a certificate of calibration to show the manufacturer is very confident of the accuracy of the product. 


Thermapen One


What’s New with The Thermapen One


The main improvements are the fact you have a one-second read time which has been reduced from 3 seconds in the previous model. This improvement is vital if you want your food cooked to perfection as a steak can change from medium to well done in seconds. So being able to get an accurate reading in one second is a great offering. 


The Thermapen One also now comes with an automatic backlight screen which if you are cooking late in the evening or even overnight being able to see the temperature of the food is a really useful feature. You can also lock the display position with horizontal or vertical whichever suits you best. 


How to use the Thermapen One


The Thermapen One is very simple to use. Simply fold out the probe and the display will automatically switch on and start to measure the temperature. The screen will only go off when you close the probe. However, if you’re busy cooking and you place the Thermapen down on the surface it will go into sleep mode which will preserve the battery. 


You do get a micro-thermocouple located at the very tip of the probe as this is where you get the measurement. You can get a reading by inserting at just an ⅛” to get a reading. 


However, in most cases you will want to insert into the thickest portion, for example in a chicken or Steak You can also test in multiple spots and with the one-second reading time, this can be done with ease. 



The Thermapen One is an ideal tool for anyone who enjoys cooking and wants to get the temperature spot on all the time. It’s fantastic for those who enjoy good old BBQ and especially useful if you’re going to take part in a cook-off. So if this is your first thermometer then this is hands down the market leader and at £66 it’s also value for money. 

Thermapen One

However, If you are familiar with the previous model the MK4 then I would question the need to upgrade. Yes, it gives you readings 2 seconds faster and has amended some of the design issues you got with the MK4 in the Thermapen One I would stick with what you have as they are the same device apart from the subtle changes. 


So if you enjoy your cooking and want that extra tool to make your food the perfect temperature every time it’s well worth investing in.


Product Rating:

  • Design: 4.0 out of 5.0 stars
  • Features: 5.0 out of 5.0 stars
  • Temperature Recording: 5.0 out of 5.0 stars
  • Value for Money : 5.0 out of 5.0 stars            

Overall Rating: 4.7 out of 5.0 stars 4.75 Stars

The ThermoWorks Thermapen One is available for £66 from

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