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Why Does Your Toaster Only Toast One Side?

A toaster isn’t supposed to only toast one side, but many models do exactly that. For a relatively simple appliance that’s been around for over a century, you would think that every brand has perfected the technology, but that’s not the case. So, why does your toaster only toast one side?

Your toaster only toasts one side due to uneven heating or infrared radiation from the nichrome wires. However, this problem could also be due to inaccurate toaster settings, the toaster’s condition, the bread’s quality, or the unavoidable Maillard reaction. 

Different types of bread don’t toast identically and may require distinct toaster settings, so you can’t expect the same results for every bread quality. However, even accurate settings may not fetch you the perfect toast. Read on to learn why your toaster only toasts one side and what you can do about it.

Reasons Why Your Toaster Only Toasts One Side

Technically, most toasters don’t toast one side. However, many toasters do only deliver one side that’s unambiguously better toasted than the other. Since there are a few variables here, I’ll discuss one issue at a time without omitting the influences of the other factors. 

Your Toaster Is Toasting Unevenly

A toaster that toasts only one side is due to uneven heating. The uneven heating may have different causes, but the resulting issue is indisputable. So, let me highlight a few reasons for a toaster heating or toasting unevenly:

  • The toaster uses radiant heating, i.e., infrared radiation, in an open appliance. Hence, you can’t expect the kind of heat regulation you have in a gas or electric oven. Even microwaves using electromagnetic radiation in an enclosed oven have hot and cold spots.
  • Both sides of a piece of bread don’t necessarily have a perfect alignment with the nichrome wires. Thinner or smaller slices, and tilting or other misalignments, can be the cause or facilitator of uneven heating, irrespective of the toaster’s condition or fault. 
  • Unclean mica bars and crumb-laden toasters. Most toasters use a heat-resistant material between the nichrome wires and the slots. Also, many toasters have a crumb tray. Significant residue buildup on these parts can cause uneven toasting. 
  • Toasting is due to the Maillard reaction, a temperature-sensitive process. If the temperature fluctuations are not suitable for the Maillard reaction in bread, you won’t have a perfect toast. However, this problem may or may not be limited to one side. 

The chemical process that turns bread brown during toasting is known as the Maillard reaction. The same process is the science behind how sugar and milk caramelize, and how roasted meat gets the color and flavor.

Essentially, the Maillard reaction is how sugars and amino acids react and combine at specific temperatures. Now, the key is temperature, so any significant fluctuation (whether high or low) won’t facilitate the Maillard reaction.

The Maillard reaction starts at around 239°F to 266°F (115°C to 130°C). Some foods undergo this process until 356°F (180°C), after which the toasting or roasting stops. However, bread tends to toast best at temperatures 285°F (140°C) to 320°F (160°C).

When you toast bread at a low or medium setting, your toaster isn’t aiming for 320°F (160°C), as such high temperatures can severely char or burn your slices. 

Thus, a lower setting may attain somewhere around or less than 285°F (140°C), which is the nominal level for bread toast. If the infrared radiant heat on a side isn’t enough to attain that temperature and sustain it, that part of your bread will not toast perfectly. 

The Nichrome Wires Are Faulty

Toasters use nichrome wires to generate radiant heat. The nickel-chromium alloy is excellent at resisting electricity to convert it to thermal energy, which is infrared in this context. Some of that energy conversion also produces visible light, which is the glow you see on the coils in your toaster.

As efficient and effective as nichrome is, the wires in a toaster may be faulty. Most toasters have slender nichrome wires that aren’t invincible. Thus, the nichrome wires may break, degrade, and lose their high resistance. 

Also, a toaster may have nicked, defective, or damaged nichrome wires on one side. This issue could be a manufacturing defect or due to improper handling. The wires or coils are vulnerable to cracking and breaking due to structural damage, or even if you use sharp and hard utensils.

Faulty nichrome wires on any side will lead to uneven toasting. These coils or wires in a toaster are aligned parallelly in a grid-like pattern. So, the toaster may continue to function even if some of the wires or parts are not heating anymore. However, you won’t have two perfectly toasted sides.

The Toaster Settings Are Wrong

Last but not least, your toaster settings affect the quality of a toast. 

First, you shouldn’t use the bagel mode for bread if your toaster has this feature. The bagel mode toasts one side and warms the other. So, ensure you don’t have the bagel or one side toast mode on, inadvertently or otherwise. 

Second, you should use the appropriate settings when toasting different types of bread. For instance, a thicker bread slice needs a higher heat or temperature setting. Likewise, colder or fresher bread needs higher temperatures and so do denser varieties. 

In contrast, you must use lower heat or temperature settings for thinner, warmer, older, or softer bread. Additionally, you should account for moisture. Bread with more moisture will require a higher temperature to toast well and evenly on both sides, while drier bread will burn at high heat. 

What To Do When a Toaster Only Toasts One Side

You can’t do anything about the Maillard reaction, and if you have broken or faulty nichrome wires, the only remedy is to replace them. However, you can proactively select the right settings for the type of bread you have. Plus, you can keep a toaster clean for maximum efficiency.

Here’s an effective approach to cleaning and maintaining a toaster:

  1. Empty the removable crumb tray as frequently as you can.
  2. Turn the toaster upside down and get rid of loose residue.
  3. Use a pastry brush or old toothbrush to gently clean the nichrome wires.
  4. Dab some vinegar on a rag or brush to clean the mica bars and slots.


Most toasters only toast one side due to uneven heating, faulty nichrome wires, and inaccurate settings. Also, a bread’s quality (including composition, density, thickness, moisture, and other elements) will affect the eventual outcome.

Additionally, an unclean toaster may not toast both sides equally well. Therefore, maintaining a clean toaster will positively impact the quality of your toast.


  • Jake Alexander

    Jake is a freelance writer from Pennsylvania who enjoys writing about science and sports. When he's not writing for Temperature Master, he can be found watching the NFL or playing basketball with his friends.

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