Why self-rising flour is really three ingredients in one
Self-rising flour is a convenience product — all-purpose flour pre-mixed with a set amount of baking powder and salt, sized for recipes (biscuits, some quick breads, classic Southern recipes) that always use those three ingredients in roughly the same proportion anyway. Mixing your own from ingredients you likely already have gives an identical result, since there's nothing special about the flour itself — it's the exact same all-purpose flour with the leavening blended in ahead of time.
Don't also add separate baking powder or salt
If a recipe calls for self-rising flour plus its own separate baking powder or salt, that's intentional — some recipes lean on extra leavening beyond what's already in the flour. Follow the recipe's full ingredient list as written; this calculator is for recreating the self-rising flour itself, not for second-guessing how much additional leavening a specific recipe wants.
FAQ
Does this work with any flour, or just all-purpose? The standard ratio is built around all-purpose flour specifically — swapping in a different base flour changes protein content and absorption, which affects results beyond just the leavening.
How long does homemade self-rising flour keep? About as long as the baking powder in it stays active — a few months in an airtight container. Mix only what a recipe needs rather than a large batch to store, since baking powder gradually loses potency over time.