All-Purpose Flour vs Cake Flour: Which One Should You Use?

In the all-purpose flour vs cake flour question, the short answer is that all-purpose flour works for most home cakes, but cake flour gives a softer, finer crumb because it has less protein. If a recipe asks for cake flour and you only have all-purpose, you can make a close substitute at home with cornstarch in two minutes.

Flour names and labels change from one country to the next, so it is easy to feel unsure about which pack to pick up. This guide explains how flours differ, what the protein number means, and which one to use for cakes, cookies, bread and more.

What is all-purpose flour?

All-purpose flour is finely milled, refined wheat flour. The bran and germ are removed, leaving the white, starchy inner part of the grain. That makes it smooth and pale, and it is the standard flour in most home kitchens and bakeries.

Depending on where you live, you may see it sold as all-purpose flour, plain flour or simply wheat flour. It is a middle-of-the-road flour that does a decent job of almost everything.

Why protein matters in flour

When flour meets water and you mix it, two of its proteins join up to form gluten. Gluten is a stretchy network that traps air. More protein usually means more gluten, which means more chew and structure.

• Bread wants lots of gluten, so it can stretch, hold gas and rise tall with a chewy crumb.
• Cakes want little gluten, so the crumb stays soft, tender and fine.

Cake flour is also milled very fine, and in some countries it is treated to help it hold more sugar and liquid. That is part of why a sponge made with it feels so light.

All-purpose flour vs cake flour: the key differences

Here are the approximate protein ranges you will see. Treat them as a guide, not exact numbers, because brands and countries differ.

Check the label on your pack

The easiest way to know what you are buying is to read the nutrition label. Look at the protein figure per 100 g. If it says around 10 to 11 g, that flour is about 10 to 11% protein. Two all-purpose brands can differ by a point or more, which is why the same recipe can behave a little differently from one pack to the next.

How to make cake flour at home

Cake flour is not stocked in every shop, but this homemade version works well. Cornstarch has no gluten-forming protein, so swapping a little in lowers the overall protein of your all-purpose flour.

1. Measure 1 cup (120 g) of all-purpose flour.
2. Remove 2 tablespoons (about 15–16 g).
3. Add back 2 tablespoons (about 15–16 g) of cornstarch.
4. Sift the mix together two or three times so the cornstarch is spread evenly.

Scale it up for bigger recipes. For 240 g of flour, use about 210 g all-purpose flour and 30 g cornstarch. Weighing is more accurate than cups, because a scooped cup of flour can easily weigh 20 to 30 g more than a spooned one.

Make sure you use cornstarch, the fine white powder (sold as cornflour in some countries), and not cornmeal or polenta, which are coarse yellow maize and will not work here.

When all-purpose flour is perfectly fine

You do not need cake flour for most home baking. All-purpose flour does a great job in:

• Butter cakes, pound cakes and tea cakes
• Most eggless cakes, which often rely on yogurt, milk and baking soda for softness
• Brownies, muffins and banana bread
• Cookies, especially chewy ones
• Tart and pie pastry
• Pizza bases and many flatbreads

Cake flour (or the DIY version) is worth it when a recipe depends on a very light, tender crumb, such as chiffon cake, genoise sponge, angel food cake or Japanese-style cotton cakes. If you bake without eggs, our eggless cakes guide shows how all-purpose flour batters stay soft.

Can you use whole wheat flour in baking?

Yes, with a few things in mind. Whole wheat flour still contains the bran and germ. That gives more flavour and fibre, but also a heavier, denser result. Bran absorbs more liquid, so whole wheat doughs and batters usually need a little more liquid than all-purpose ones.

• Start by replacing about a quarter to half of the all-purpose flour with whole wheat in cakes and cookies.
• Expect a nuttier taste and a slightly darker, denser crumb.
• For 100% whole wheat bakes, choose recipes written for whole wheat, since they are balanced for it.

Other flours you might see on the shelf

• Self-raising flour is flour with baking powder (and usually salt) already mixed in. Do not use it in place of all-purpose flour unless you reduce or remove the baking powder in your recipe, or your cake may rise too fast and sink.
• Pastry flour sits between cake flour and all-purpose flour in protein. It is handy for tender pie crusts and biscuits, but all-purpose flour works fine for these at home.
• Semolina is coarser and made from durum wheat. It is great in semolina cakes, pasta and some breads, but it is not a swap for all-purpose flour in a sponge.

Storing flour so it stays fresh

Flour picks up moisture and smells from the air, and in warm, humid weather it can attract insects. Move it from the paper packet into an airtight container. Whole wheat flour contains natural oils from the germ, so it goes stale faster than all-purpose flour. Buy it in smaller amounts, or keep it in the fridge in a sealed box and let it come to room temperature before baking.

Bread flour for breads

For tall, chewy loaves, bread flour is the better choice. Its higher protein builds the strong gluten that holds gas during a long rise. All-purpose flour can still make good soft breads like dinner rolls, but for crusty loaves and sourdough, bread flour gives better structure. Sourdough bakers can read more in our guide to fixing a sourdough starter that is not rising.

Want to understand flours, mixing and structure properly instead of guessing? The APCA Chef Online Pastry Program covers these basics with chef guidance.

Frequently asked questions

Read next

• Eggless Cakes
• Sourdough Starter Not Rising? 7 Fixes That Actually Work
• Online Baking Course: What Actually Determines Whether You Learn Anything