Built-in oven dials commonly run 25 degrees or more off true temperature, which is why an independent oven thermometer is worth owning even on a new range. Candy and deep-fry thermometers are a separate, single-purpose tool for sugar-stage work like caramel and Italian meringue.
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Taylor
The simple, well-known analog dial thermometer that hangs or stands on a rack. The large dial is easy to read, but like most analog dials it can drift a few degrees over years and is worth rechecking against a boiling-water test occasionally.
CDN
NSF-certified accuracy and a shatter-resistant lens make it more durable than a basic dial thermometer. The dial face is a bit smaller than some competitors, which makes it slightly harder to read from across the kitchen.
Rubbermaid
A commercial-grade stainless dial thermometer built for restaurant ovens, so it tends to hold calibration well over time. The dial is utilitarian, not designed to look decorative sitting on a rack.
CDN
Essential for candy-making, where a few degrees changes the sugar stage entirely. The pot clip and long stem keep your hand away from hot sugar, but it's a single-purpose tool, not a substitute for an oven thermometer.
ThermoPro
A digital dual-probe design lets you monitor oven air temperature and a food probe at once, with an alarm, more precise and easier to read at a glance than an analog dial. It needs batteries and is a more complex tool than a simple hang-on dial for bakers who just want a passive check.