The protein content of flour varies not only with the kind of flour, but the type. Here is a list of the most commonly used flours, their protein content and recommended uses:
Whole wheat flour – 14% protein – use for heavier hearth breads and blending with other flours (blending all-purpose flour with whole wheat makes it easier to raise bread).
Bread flour – 12% – 13% protein – breads, bread machine breads and pizza dough. This flour has a higher gluten content.
All-purpose flour – 9% – 12% protein – everyday cooking, quick breads, pastries (don’t use bleached).
Self-rising flour – 9% – 11 % protein – biscuits, quick breads, cookies.
Pastry flour – 8% – 9% protein – pie crusts, pastries, cookies, biscuits (this does not include whole wheat pastry flour).
Cake flour – 5% – 8% protein – cakes.
High-Gluten flour – 14% – 15% protein – bagels, pizza crust and blending with other flours. I also like it in the bread machine
Look at the flour packaging for nutritional information. Different brands of the same type of flour can have different protein content as well.