T45, T55, T65: What the Number on Your Flour Bag Really Means

The type of a French flour (T45, T55, T65 and beyond) measures its ash content, meaning the amount of minerals left when you burn 100 g of flour at very high temperature. In practice, the higher the number, the more whole-grain the flour: more of the wheat's bran and germ, so more fiber, more minerals and a stronger flavor.

It's not a quality ranking. It's a ranking by use.

T45: the whitest, finest flour

T45 is milled very fine, with almost no bran. It has plenty of gluten, stretches well and absorbs a lot of liquid. It's the flour for viennoiseries (croissants, brioche), macarons, puff pastry and thin crêpes. The closest US equivalent is pastry or cake flour. For everyday bread or a rustic cake, it lacks flavor and character.

T55: the everyday flour

This is the standard flour sold in supermarkets labeled simply wheat flour. It's versatile and works for cakes, tart dough, sauces (béchamel, roux) and cookies. It has less gluten than T45, so doughs are slightly less elastic, which is a plus for shortcrust and sweet doughs. Think of it as the French all-purpose flour.

T65: for artisan bread and pizza

More bran, more flavor. T65 gives bread a slightly creamy crumb, a more pronounced crust and a much better aroma than T55. It's the flour of the French baguette de tradition, and it's close to US bread flour. It's also widely used for pizza. Authentic Neapolitan pizza is made with Italian 00, which roughly corresponds to a T55 to T65, with long gluten that stands up to a long fermentation.

T80, T110, T150: semi-whole and whole-grain flours

T80 (semi-whole): good for country bread, savory crêpes, rustic pancakes. T110 (light whole wheat): whole-grain bread, muffins, cookies with character. T150 (whole wheat): dense whole-grain bread, crackers, buckwheat galettes. The more whole-grain the flour, the more water it absorbs and the denser the finished product. A whole-grain flour is often blended with T65 to keep things light while adding flavor: 70% T65 plus 30% T110 makes a very good homemade bread.

Can you substitute?

T45 for T55: in most cakes and doughs, yes, with no adjustment. T55 for T65: in bread, add 5 to 10% more liquid (T65 absorbs more). T55 for T110: only as a blend, never as a straight swap in cakes. To lower the glycemic index without changing your habits: replacing a third of the white flour with T110 in cakes and breads is almost invisible in texture, but significant nutritionally.

How to choose in practice

For a cake, crêpes or a béchamel, T55 works. For puff pastry or brioche, T45. For a homemade bread with more flavor, T65, or a blend with a little T110. The type is printed on the bag, and a bag that says only "wheat flour" is generally T55.

Storage

Store flour somewhere dry, away from humidity and heat, in a closed container. Whole-grain flours, which contain fat-rich germ, keep less well than white flours: buy them in smaller quantities.

Frequently asked questions

Which flour for tart dough? T55, which gives a less elastic dough: see our homemade pie crust. What does the number mean? The ash content, so the amount of minerals, not quality. Can I swap T55 for T65? Yes in most cases, with a less flavorful bread.