Our Culinary Team Explains the (Very Important!) Difference

I’ve never known my parents’ pantry to be without large (very large) bags of all-purpose flour and bread flour. When I was growing up, my mom would often use AP flour to make a simple dough for manaeesh, a Middle Eastern round flatbread typically topped with cheese or za’atar. She usually used bread flour whenever we decided to make a homemade pizza, and I always noticed that we went through it at a much slower pace than all-purpose flour, but I didn’t fully grasp the difference between the two types of flour until I became an editor at Serious Eats. 

Both bread flour and all-purpose flour have specific uses in the kitchen, and it’s important to know how their differences can affect your baking and cooking—because they can affect it very much. “The rule of thumb is never replace one kind of flour with another in a recipe—it can really mess things up,” says Editorial Director Daniel, who never misses a chance to nerd out about the science of proteins in flour. I also spoke with Culinary Editor Genevieve, who has trained and worked as a baker, to learn more about these differences and how to use each in recipes. 

The Key Difference Between All-Purpose and Bread Flour and All-Purpose Flour: It’s All About Protein

The biggest difference between all-purpose and bread flours is their protein content. The protein content in bread flour ranges from 12 to 14%, the highest amongst refined wheat flours. All-purpose flour, on the other hand, contains a moderate protein content of 9 to 12%, making it a much more versatile flour option. These protein levels directly relate to how much gluten the flours can produce, which determines the structure and chewiness of the finished baked goods.

Gluten is formed when two proteins, glutenin and gliadin, are mixed with water or another water-based liquid. The higher the protein content, the more gluten development there can be. Lower-protein flours are preferable for tender baked goods like muffins, biscuits, cookies, and cakes, for example, since too much gluten would make them tougher and chewier. Higher-protein flours, on the other hand, can produce stronger, more elastic doughs that are critical for a better crumb and rise in crusty breads, pizza doughs, and bagels—it’s the strength and elasticity of a high-gluten dough that improves its ability to trap gas bubbles and form puffy air pockets during baking. 

The tricky thing about bread and AP flours is that there are no strict rules, meaning the exact protein percentage depends on the brand. This is why our recipes sometimes call out certain brands of flour. For example, King Arthur sells an all-purpose flour that has an unusually high protein content verging on bread flour levels. As much as we love King Arthur products, we tend to avoid their AP flour for this reason—it’s just too much of an outlier. (Our baguette recipe is just one exception to this, as it calls for a high-protein AP flour for a proper crisp and tender texture, and King Arthur, with its higher-than-normal 11.7% protein amount, fits the bill.)

A safer bet for AP flour is a brand like Gold Medal, which is 10.5% protein, a nice sweet spot as far as all-purpose flours go (and no, they’re not paying us to say this!). For breads where you want a more tender texture, go for AP flour with a lower protein content, like White Lily.

Common Uses for Bread Flour and All-Purpose Flour

There are no hard-and-fast rules about whether you should use bread or AP flour in any given recipe—in the hands of a knowledgeable baker, many recipes can be made to work either way, and AP flour in particular is a versatile flour that can appear in recipes ranging from delicate pastries to hearty sourdough loaves (it is all-purpose, after all). That said, the two flours have different advantages that can make them more or less appropriate for various recipes.

Bread flour, as the name suggests, is used to make sturdier doughs for breads, bagels, and pizza; bread flour may also appear in recipes for more tender, fat-rich doughs like challah because their fat content inhibits gluten formation, something of a balancing act that helps to arrive at a loaf that’s both tender but also substantive. However, not all bread recipes require bread flour. Fluffier breads (both sweet and savory) like focaccia and cinnamon rolls lean on AP flour, but if you’re interested in making challah or certain flatbreads regularly, then you’ll want to keep a bag of bread flour on hand. 

All-purpose flour is a more versatile flour, and is often a preferred choice for recipe developers, including our own, since it’s safe to assume most people already have it in their pantry. “There’s a reason it’s called all-purpose,” says Genevieve. “I use it for most baking” Many of our bread recipes, including white bread, sourdough, and Parker House rolls, call for AP flour since it’s possible to formulate great recipes using it without requiring something like bread flour, which home cooks are less likely to have at home.

Can You Substitute All-Purpose for Bread Flour, and Vice Versa?

It’s always best to follow recipe guidelines, and we don’t recommend swapping one flour for the other unless you’re a skilled baker and know how to adjust accordingly—the protein difference between bread and all-purpose flour means they often require different levels of hydration and methods of handling. It is frequently not as simple as a 1:1 swap. However, we’ve previously tested mixing AP flour with vital wheat gluten as a substitute for bread flour, and it works in a pinch (this was especially helpful during the pandemic, when everyone was making sourdough and bread flour was frequently out of stock). 

“Recipes with flour are formulated carefully for a specific type of flour and swapping one for another is not at all a given,” says Daniel. “If you do swap, be prepared to not be happy with your results, and blame no one but yourself.” Genevieve adds that if you swap bread flour in place of AP flour, “expect whatever you’re making to be quite bready. Which might be fine for a bran muffin or banana muffin but probably not ideal if that’s not what you’re going for.”

The Takeaway

Bread and all-purpose flour differ in their protein contents. Bread flour contains a range of 12 to 14% protein, while all-purpose flour is slightly lower at 9 to 12%. This difference in protein may seem small, but it can produce remarkably different results. This means it’s important to use the right type of flour called for in a recipe to ensure the best results. So while I know I’ll go through a bag of AP flour much quicker than bread flour—especially with all the manaeesh my mom makes—I always keep bread flour on hand for whenever it’s time for a pizza night.