What's the difference between Italian Type 00 Flour and All-Purpose Flour?

Italian Type 00 Flour: 11.00-12.50% protein, absorption 1.010×, hydration 58-68%. All-Purpose Flour: 10.50-11.70% protein, absorption 0.970×, hydration 60-72%.

Can I substitute Italian Type 00 Flour for All-Purpose Flour 1:1?

Not directly. Absorption differs by 4.1%, so Italian Type 00 Flour needs more water. Adjust hydration by 4% when substituting.

Which is better for open-crumb sourdough?

All-Purpose Flour supports higher hydration (up to 72%), making it better suited to open-crumb hearth loaves than Italian Type 00 Flour (max 68%).

Side-by-side comparison

Italian Type 00 Flour vs All-Purpose Flour

	Italian Type 00 Flour	All-Purpose Flour
Protein	11.00–12.50%	10.50–11.70%
Absorption (× bread flour)	1.010	0.970
Hydration range	58–68%	60–72%
Category	refined-wheat	refined-wheat
Ash %	0.45	0.48

Italian Type 00 Flour

Italian Type 00 is the finest-ground wheat flour category in the Italian classification system. Low ash content (0.45% max), very fine particle size, protein typically 11-12.5% for pizza and 13-14% for bread variants. Caputo's Pizzeria 00 (11-12%) is the global reference for Neapolitan pizza dough. Caputo Pizza Napoletana Cuoco (13-13.5%) is the bread-focused variant. Absorption is marginally higher than bread flour (1%) due to fine grind. Optimal for pizza (60-65% hydration), focaccia (75-80%), and sandwich loaves (65-68%).

All-Purpose Flour

All-purpose flour (AP) sits between cake flour and bread flour in protein content. At 10.5-11.7% protein, it produces softer sourdough with more tender crumb but less oven spring than bread flour. Absorption is ~3% lower than bread flour baseline. King Arthur's AP is the US reference (11.7% protein); Gold Medal and Pillsbury run slightly lower (10.5-11%). Use AP when you want a softer hearth loaf, a sandwich-style sourdough pan loaf, or when blending into enriched doughs like brioche. AP absorbs less water — recipes designed for bread flour need hydration reduced by ~3% when substituting AP.

Substitution math

When substituting Italian Type 00 Flour for All-Purpose Flour in a recipe, adjust hydration by about 4% — add more water because Italian Type 00 Flour absorbs more than All-Purpose Flour.

The gear that makes the math work

A short, honest baking kit. The scale matters most — every weight on this page is in grams. The Dutch oven is what turns a good crumb into a great crust.

Digital kitchen scale (0.1 g)
Baker's percentage is by weight, not volume — a 0.1 g scale is what makes the math on this page accurate.
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Dutch oven / combo cooker
Traps steam for the first bake phase — the single biggest factor in oven spring and a blistered, glossy crust.
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Banneton proofing basket
Wicks moisture and holds shape during the final proof, so high-hydration dough doesn't spread flat.
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Bread lame + bench scraper
A sharp lame scores clean ears; a steel bench scraper handles wet, sticky dough without tearing the gluten.
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High-protein bread flour
The math assumes ~12–14% protein. Real bread flour absorbs the hydration you calculate — all-purpose won't.
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Danish dough whisk
Mixes shaggy, high-hydration dough in seconds without the gluey mess of a spoon or your hands.
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🎧 Or learn the craft by ear

The numbers here are the what; a good baking book is the why. An Audible trial gets you any title free — Michael Pollan’s Cooked(the “Air” chapter is the best story ever told about why bread rises) is a perfect first listen.

Start a free Audible trial →

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Gear guides — what actually matters