Flour Substitution

Amount

Recipe Calls For

You Have

Substitution

Excellent Match

1 cupAll-Purpose Flour

0.88 cupCake Flour

Also Add:

++ 2 tbsp cornstarch per cup

Measure 7/8 cup AP + 2 tbsp cornstarch = 1 cup cake flour.

Flour Types Guide

All-Purpose Flour

10-12% protein

Versatile, most common flour. Works for almost everything.

Bread Flour

12-14% protein

High protein for strong gluten. Creates chewy texture.

Cake Flour

7-9% protein

Low protein, finely milled. Creates tender, delicate crumb.

Pastry Flour

8-10% protein

Between cake and all-purpose. Flaky, tender results.

Whole Wheat Flour

13-14% protein

Contains bran and germ. Nutty flavor, denser texture.

Self-Rising Flour

8-9% protein

All-purpose + baking powder + salt. Convenience flour.

Gluten-Free Blend

Varies protein

Mix of rice flour, starches, and gums. For gluten sensitivities.

Almond Flour

21% protein

Ground blanched almonds. Moist, dense, nutty flavor.

Understanding Flour Types

It's All About Protein

The main difference between flour types is protein content. Higher protein means more gluten when mixed with water. Bread flour (12-14%) makes chewy bread; cake flour (7-9%) makes tender cake.

Why Substitution Works

By adjusting ratios and adding starches (which reduce gluten development), you can approximate one flour with another. Results may differ slightly, but substitutions work for most home baking.

Common Substitutions

Cake Flour ⅞ cup AP + 2 tbsp cornstarch

Bread Flour AP + vital wheat gluten

Self-Rising AP + baking powder + salt

Flour Substitution by Weight: The Numbers Behind the Swap

Volume is the reason flour substitutions go wrong. A "cup" of all-purpose flour can weigh anything from roughly 100 g to 145 g depending on whether it was scooped, spooned or sifted — and a two-tablespoon error is enough to turn a tender cake into a tough one. Every swap below is written as a weight ratio, so you can scale it to any recipe size and use the unit converter when the recipe only gives cups.

One cup of flour on a scale, and what changes when you swap it in (King Arthur Baking ingredient weight chart and product specifications).
Flour	1 cup weighs	What changes when you swap it in
All-purpose	120 g	The default. 11.7% protein in the brand tested — strong enough for bread-ish doughs, weak enough for cookies and quick breads.
Bread flour	120 g	12.7% protein. Swaps 1:1 by weight or volume for all-purpose in a pinch; the dough absorbs slightly more liquid, so the crumb comes out a little tighter.
Cake flour	120 g	10% protein — the tenderest of the three. Fine to use all-purpose instead; the reverse (cake flour into a bread recipe) risks a sunken or crumbly result because it cannot build enough gluten.
Whole wheat (100%)	113 g	Bran interferes with gluten, so whole wheat loaves are usually paired with a stronger flour — a 50/50 whole wheat and bread-flour blend was tested to give a better structure and rise than whole wheat and all-purpose.
Self-rising	113 g	Already contains baking powder and salt, so do not add more leavening on top of it. Swap it for all-purpose only after adjusting the recipe's leavening.
Pastry flour	106 g	Lighter than all-purpose, heavier than cake flour. Good 1:1 by weight for pie dough and biscuits that should stay flaky rather than chewy.
Cornstarch	112 g	Not a flour substitute on its own — it is the tenderiser in every do-it-yourself cake flour blend (see the ratio below).

Worked conversions

2½ cups all-purpose, but the shelf only has bread flour? Bread flour weighs the same per cup, so the swap is 1:1 — 2½ cups (300 g) of bread flour for 2½ cups (300 g) of all-purpose. Expect a slightly chewier result and be ready to add a splash of water if the dough feels stiff.

60 g of cake flour, built from all-purpose plus cornstarch? The published blend is 105 g all-purpose whisked with 14 g cornstarch to stand in for 1 cup (about 120 g) of cake flour. Scaled down: 60 g cake flour ≈ 53 g all-purpose + 7 g cornstarch, whisked together twice so the starch is evenly distributed.

Measuring by spoons instead? That same blend is 3/4 cup + 2 tablespoons all-purpose plus 2 tablespoons cornstarch — the starch lowers the overall protein of the mixture to mimic cake flour and adds tenderness.

Making self-rising flour from all-purpose? Whisk 1 cup (120 g) all-purpose with 1½ teaspoons baking powder and ¼ teaspoon salt for each cup of self-rising flour the recipe calls for.

One caveat that matters more than the math: published weights and protein percentages are brand-specific. Milling companies blend different wheat, and substituting one brand's bread flour for another brand's all-purpose can move the protein level by two to three points, which is enough to change how a loaf rises. Check the bag you actually own, and once you have the weight, scale the whole recipe rather than adjusting one ingredient in isolation. For leavening maths that pair with these flours, see the yeast converter and bread proofing calculator.

Flour Substitution Calculator