Gear guide
Best flour for sourdough
The flour is the dough the math is written for. Get the protein right and a slack 75% dough holds together and springs; get it wrong and the prettiest formula still bakes flat. One number decides most of it.
The short answer: The best flour for sourdough is an unbleached white bread flour around 12–13% protein — enough gluten to hold the hydration and trap the gas. Want more open crumb? Go 13–14% artisan. Want flavor? Blend in 10–30% whole wheat. Protein is the number that matters; the brand just needs to be consistent.
What actually matters
- 1. Protein (the one number)
Bread flour ~12–14% vs all-purpose ~10–11%. Protein builds the gluten that holds high hydration and traps gas. This decides more than the brand on the bag.
- 2. Bread vs all-purpose
Use bread flour. All-purpose bakes a denser, flatter loaf — especially as hydration climbs. The whole site's math assumes real bread flour.
- 3. White vs whole grain
Mostly white for structure; blend 10–30% whole wheat or rye for flavor + a livelier ferment. 100% whole grain is denser and thirstier — great later, hard as a first loaf.
- 4. Consistency over prestige
A consistent brand = repeatable loaves. Unbleached beats bleached for dough. Organic/specialty is about sourcing, not a better crumb at the same protein.
What to skip: bleached flour (it can weaken dough), self-rising flour (it has added leavening + salt — wrong for sourdough), and chasing exotic specialty flours before a plain bread flour bakes you a consistent loaf. Nail the protein first; experiment with the fancy stuff later.
The picks, by what you want
- Best overall · the defaultWorkhorse white bread flour (~12–13% protein)
A consistent, unbleached white bread flour in the ~12–13% protein range is the dough every recipe on this site is written for. It absorbs the hydration you calculate and builds the gluten that traps the gas — King Arthur Bread Flour (~12.7%) is the widely-available US benchmark, and brand consistency means a loaf you can repeat, not one you got lucky with.
Watch out: Check it says 'bread flour', not 'all-purpose' — and unbleached. All-purpose (~10–11%) can't hold a high-hydration dough.
Compare on Amazon → - Best for open crumb & high hydrationHigh-protein artisan / professional bread flour
Step up to a professional-grade high-protein artisan flour (the kind small bakeries use) when you push hydration higher or want a more open, chewy crumb. The extra gluten strength holds more water and a longer fermentation without the dough going slack.
Watch out: Higher protein wants more water and more dough strength — adjust hydration up gradually rather than all at once.
Compare on Amazon → - Best for flavor & a faster, livelier fermentWhole-wheat / whole-grain bread flour
Whole grain brings flavor, more nutrition, and wild-yeast food that wakes up a starter — most bakers blend 10–30% into white flour rather than going 100%. Stone-ground whole wheat is the classic choice for that nutty, tangy country loaf.
Watch out: Whole grain drinks more water and ferments faster — raise hydration and shorten the bulk a touch, or the loaf turns dense and gummy.
Compare on Amazon → - Best if you care about sourcingOrganic / regeneratively-milled flour
If sourcing matters to you, certified-organic unbleached bread flour bakes identically to conventional at the same protein level — you're paying for the farming and milling story, not a different loaf. A fine choice; just match the protein tier above.
Compare on Amazon →
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Compare flour types in depth — protein, absorption & hydration by flour →
🎧 The flour is half the storyKnowing how a flour behaves — why protein, why whole grain ferments faster — is what turns a bag of flour into a great loaf. Maurizio Leo’s The Perfect Loaf and Ken Forkish’s Flour Water Salt Yeast are on Audible, and a free trial gets you one to listen to while your dough proofs.
Start a free Audible trial →
Common questions
What flour is best for sourdough?
An unbleached white bread flour in roughly the 12–13% protein range is the best all-round choice — it has the gluten strength to hold the high hydration sourdough needs and to trap the gas for a good rise. Many bakers then blend in 10–30% whole wheat or rye for flavor. All-purpose flour can work for a simpler loaf but bakes flatter; the protein is the number that matters most.
Bread flour or all-purpose for sourdough?
Bread flour. The difference is protein: bread flour sits around 12–14%, all-purpose around 10–11%. That extra protein builds the gluten network that holds a slack, high-hydration sourdough together and traps the carbon dioxide for oven spring. You can bake sourdough with all-purpose, but you'll get a denser, flatter loaf — especially at higher hydration.
What protein percentage should sourdough flour have?
Aim for about 12–14% for white bread flour. Around 12–13% (e.g. King Arthur Bread Flour at ~12.7%) is a forgiving, versatile target; higher-protein artisan flours (13–14%) hold even more water and give a more open, chewy crumb but want a stronger hand. Below ~11% (all-purpose) the dough struggles to hold hydration.
Should I use whole wheat or white flour for sourdough?
Most bakers use mostly white bread flour with a whole-grain blend — typically 10–30% whole wheat or rye — for the best of both: structure from the white, plus flavor, nutrition, and a livelier ferment from the whole grain. A 100% whole-wheat loaf is denser and needs more water and a shorter bulk; great once you've got the technique, harder as a first loaf.
Is organic or expensive flour worth it for sourdough?
For the loaf itself, no — what matters is protein and freshness, and a good conventional bread flour at the right protein bakes just as well. Organic or specialty-milled flours are worth it if you value the sourcing and farming, not because they produce a better crumb at the same protein level. Spend on consistency and the right protein first.
The rest of the bake-day kit
Got the flour? Weigh it, shape it, bake it.