7 toaster oven mistakes to avoid at all costs

A toaster oven in a kitchen with a hand pulling the door down
(Image credit: Shutterrstock)

Toaster ovens are versatile appliances to say the least. Depending on the model, some can air fry, toast, bake, roast and broil. That’s why they’re often purchased over the best air fryers — you’re getting several appliances in one. And while toaster ovens are relatively easy to use, take care, because there are still mistakes often made with these machines — mistakes that can even impair the best toaster ovens

Make any one of these errors, and it can impact your cooking results, leaving you with a less-than-delicious dish. In the worst case scenario, some can even lead to a fire hazard. So it’s imperative that you avoid these common mistakes; that way you can get the best experience from your toaster oven. Here are 7 toaster oven mistakes to watch out for.

1. Overcrowding 

Bread being toasted in a toaster oven

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One of the main benefits of a toaster oven compared to an air fryer is the space on offer. With a drop down door and an internal cavity, much like a microwave, space is plentiful compared to the average air fryer basket. Toaster ovens generally list their capacities in terms of pounds of turkey or slices of bread, with the largest ranging up to about 9 slices or even two small birds. While this is adequate to feed a family, some will still overfill this space, especially when hosting for a large party. However, this is a big mistake to avoid. 

An overcrowded toaster oven won’t be able to cook the food evenly or consistently. If you have an air fryer function, the air needs to circulate the food to cook effectively, and if everything is crammed together or piled up, this won’t happen. Even when toasting bread, if slices overlap, they won’t be grilled at the same rate. This could even lead to a potential fire hazard should the toaster oven overheat as a consequence, or should food be exposed to the heating elements. So always stick to your capacity. 

If you need more space, opt for a toaster oven with a larger capacity and multiple shelf levels to make best use of the room. Failing that, it’s always better to cook in batches, or even just to cook in the oven instead.      

2. Cooking things you shouldn’t 

Cooking pasta in water and using a sieve to drain the water

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While multi-functional toaster ovens can cook pretty much anything, there are still items of food that shouldn’t go in there. In such cases, these items can become fire hazards — or at the very least, they won’t cook effectively, so you should always steer clear. For one, greasy or overly fatty foods should be avoided, especially if your toaster oven has exposed heating elements at its base; these can drip as they cook and start a fire. Uncooked rice and pasta is not going to work in a toaster oven either because it needs boiling in water first — one of the best electric kettles can help with this. 

Watch out for the cookware you’re using in your toaster oven too — some of these will be unsuitable depending on the setting and temperature you’re using. Glass dishes, such as ramekins, can splinter and crack in the heat for instance. Make sure whatever you use is toaster oven safe, or stick to the accessories supplied by the manufacturer. 

 For more info, check out 9 things you should never put in an air fryer.  

3. Not cleaning it

A spray bottle and sponge held in rubber gloves

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Every kitchen appliance which comes into contact with food needs cleaning regularly, and toaster ovens are no exception. With every dish we cook, crumbs can spill, splatters can hit the walls and odors can linger. Cleaning your toaster oven after each use can help prevent stains from burning on and contaminating future meals, plus it can help keep your toaster oven working at its best. In extreme cases, a dirty toaster oven can fail to fully function and it can even start a fire from excess crumbs. 

Follow your manufacturer's instructions in terms of cleaning your toaster oven between uses. Some come with dishwasher-safe parts to make things easier, otherwise hand washing will be necessary. Remember to deep clean your toaster oven once a week with regular use too. Unplug the appliance, then soak the rack, crumb tray any accessories to get rid of stubborn burnt-on residue. Clean the inside of the appliance with a soft microfiber cloth and warm water, with a few drops of soap, avoiding the heating elements in the process. Then rinse with a damp microfiber cloth and leave to dry.  

4. Not preheating it 

A toaster oven preheating with nothing inside next to bread

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While preheating your toaster oven isn’t exactly required, it will make all the difference to your meals. By ensuring your ingredients are cooked at the right temperature for as long as needed, the results are less likely to be over- or under-cooked. Some premium toaster ovens, like the Ninja Foodi Smart XL Pro Air Oven ($329, Ninjakitchen.com), actually show they’re preheating on the display, so you know when the internal temperature has been reached. This model will even make an audible noise to inform you. 

Otherwise, you can set yourself a timer and give your toaster oven 5 minutes to reach temperature. This will use more energy versus loading the food immediately, but you can better guarantee the finish. Alternatively, you can load from the start, but you will need to monitor the food through the door. Try not to open and peak though, else you will lose the heat and the energy you were trying to save in the first place. Preheating isn't a necessity if you're just toasting bread though.

5. Not taking advantage of every setting 

A toaster oven's control panel, filled with pastry

(Image credit: Shutterstock)

Toaster ovens are often purchased because of the abundant amount of functions on offer — so, why do we usually stick to the same settings? If you plan to air fry more than anything, a dedicated air fryer would be the better option; it’s cheaper, smaller, uses less energy and tends to provide better results on this setting. But, toaster ovens can cook so much more — roast chickens, yellow cakes, and even pizzas are possible. So give your toaster oven a chance to shine, and take advantage of those unused settings. 

Toaster ovens take up a lot of countertop space, so it shouldn’t be gathering dust or going unused. If you’re considering purchasing a toaster oven, make sure you intend to use all of its functions — or else what may seem like great value will just be a waste of money.

6. Leaving it unattended 

A plug being pulled from a power point

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Toaster ovens may have come a long way in recent years. But, it’s still a piping hot appliance which could become a safety hazard or even a fire hazard in the wrong circumstances. So, you should never leave it unattended in use, not even for a moment. The glass doors become surprisingly hot — hot enough to burn young hands or any curious pets. In fact, in our tests, we recorded temperatures as hot as 278°F on the glass for one model and 339°F for the bottom front of the appliance for another. So keep an eye on your kids and pets as you use your toaster oven.

If the toaster oven can’t effectively vent in use, which can happen if it’s crowded on a surface, it can overheat and lead to a fire hazard. Make sure you follow your manual’s guidance in terms of placement to prevent this, giving it good air circulation, such as near an open window. An electrical fault in itself can lead to smoking and sparking too, so you should never be far away whatever the case. Remember to unplug your toaster oven when not in use.    

7. Buying the wrong toaster oven 

Breville Smart Oven Air Fryer Pro sitting on a counter with fresh muffins

(Image credit: Breville)

Finally, another mistake you can make is buying the wrong toaster oven in the first place — not just in terms of functionality, but also in terms of performance. We’ve tested a range of toaster ovens to find those that deliver great results across every setting. We cooked a whole host of recipes to assess this, from your classic frozen French fries, to the more unorthodox Brussels sprouts. We filled each model with toast, baked a full yellow cake and even roasted a whole chicken, so we know for sure which provides the best results.

Plus, we took the surface temperatures, noise, ease of cleaning and the general design into account too. As a result, we’ve found the best models to suit every circumstance, whether you’re shopping on a budget, or want the biggest capacity possible. See our results on the best toaster ovens page. 

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Katie Mortram
Homes Editor

Katie looks after everything homes-related, from kitchen appliances to gardening tools. She also covers smart home products too, so is the best point of contact for any household advice! She has tested and reviewed appliances for over 6 years, so she knows what to look for when finding the best. Her favorite thing to test has to be air purifiers, as the information provided and the difference between performances is extensive.