You can rely on the opinions of a professional candy maker or a pastry chef about these products. After going through several reviews of candy thermometers by professionals, we have found out that users rely on the following three things when it comes to candy thermometers:

• Easy-to-read: Most round-faced candy thermometers with a polycarbonate lens are not only waterproof but shatterproof as well. It is easy to read them at a glance, and hence they are perfect for a busy candy maker who has to make large batches of candy every day. Moreover, this product has a target range indicator along with a color-coded scale, which makes it easier to use.

• Manual vs. digital gauges: There are two kinds of gauges in a candy thermometer: manual and digital. As the digital ones record the temperature much faster than the manual ones, a digital one is preferable when you intend to produce a large quantity of candy.

• The shape of the thermometer: You should select the shape of the product depending on how you plan to use the thermometer. For example, long and wide thermometers are more appropriate for large pans and bowls. The delicate, thin and short ones can be used to reach areas which are hard to get in smaller saucepans.

• Search for an accurate device: When it comes to making candy, accuracy is of prime importance. Attach the thermometer to the pot, and look at the thermometer to make sure that the bulb is not touching the bottom of the cooking pot (that would give an inaccurate reading, as well as possibly damage the thermometer). The temperature range should read between 38 to 204 degrees Celsius (100 to 400 degrees Fahrenheit). If there is a slight inaccuracy in the thermometer, it will produce candy of a totally different texture and undesirable results.
• Test the product: The best way to know whether the product will suit your needs is to place it inside a cold water-filled saucepan. Once the water reaches boiling point, see whether the temperature reads as 37.8 degrees Celsius (100 degrees Fahrenheit). If it is not accurate, the item should be replaced.
• Think about usage: If you plan to make a lot of candy and use your thermometer often, you should invest more money on a quality product. The best ones might not come cheap, but they will last longer.
• Look at the material: Candy thermometers can be made of metal, glass and even heavy-duty plastic. The material with which it is made often affects the accuracy and speed in which the temperature is measured. A stainless-steel thermometer is known to be both quite reliable and durable. 

Polder: This brand aims to make products which can decrease the amount of effort in everyday tasks. They are known for their simple yet innovative products. The Polder THM-515 stainless steel candy/jelly/deep-fry thermometer is known to be quite sturdy and has an adjustable clip which can be adjusted according to the height of the cooking pot. The best thing about this product is its insulated handle which doesn't conduct heat.

Anpro: The digital Anpro DT-10 instant-read thermometer has an LCD panel which displays the accurate temperature. The auto shutdown feature enables the equipment to automatically shut off after a period of time—that saves battery power. It has a long probe, which makes it easier to insert it into deep pots. This water-resistant product is known for its durability.