What's the difference between Bread Flour and Italian Type 00 Flour?

Bread Flour: 12.00-13.50% protein, absorption 1.000×, hydration 65-78%. Italian Type 00 Flour: 11.00-12.50% protein, absorption 1.010×, hydration 58-68%.

Can I substitute Bread Flour for Italian Type 00 Flour 1:1?

Yes — absorption is close enough that a 1:1 swap works with minor tweaks.

Which is better for open-crumb sourdough?

Bread Flour supports higher hydration (up to 78%), making it better suited to open-crumb hearth loaves than Italian Type 00 Flour (max 68%).

Side-by-side comparison

Bread Flour vs Italian Type 00 Flour

	Bread Flour	Italian Type 00 Flour
Protein	12.00–13.50%	11.00–12.50%
Absorption (× bread flour)	1.000	1.010
Hydration range	65–78%	58–68%
Category	refined-wheat	refined-wheat
Ash %	0.50	0.45

Bread Flour

Bread flour is the workhorse of hearth-style sourdough. Milled from hard red winter or hard red spring wheat, it provides the 12-13.5% protein content needed to develop the robust gluten structure that supports open crumb and high hydration doughs. The absorption multiplier is the industry baseline (1.000) — all other flour hydration behaviors are measured relative to bread flour. King Arthur's classic unbleached bread flour and Central Milling's Artisan Bakers Craft are the reference specs for US bakers. Use it as 100% of the flour in baguettes and country loaves, or as the base (70-90%) in whole-grain blends. Bread flour tolerates extended autolyse, long bulk ferments, and retarded proofs without losing structure.

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%).

Substitution math

When substituting Bread Flour for Italian Type 00 Flour in a recipe, absorption is close enough that a direct swap works. Expect minor texture differences but similar handling.