What is the ratio of water to flour for bread?

Baker's percentage explained

In baking, water-to-flour ratios are expressed as a percentage of flour weight. This is called "baker's percentage" and is the canonical way professional bakers communicate dough hydration. So if a recipe is "70% hydration," it means: 70g water per 100g flour, or 700g water per 1000g flour.

Why this beats cups or fractions

Cups vary by 25%+ between bakers (see /pages/how-to-convert/cups-to-grams-flour). Percentages are exact + scalable. A recipe at 70% hydration produces identical dough whether you make 100g, 1kg, or 100kg of bread.

Hydration ranges by bread type

The science of hydration

• Lower hydration (50-65%): dense crumb, easy to shape, slower fermentation. Used for: bagels, pretzels, sandwich bread.
• Medium hydration (65-72%): balanced crumb, manageable for home bakers. Used for: French country loaf, baguettes, focaccia.
• High hydration (72-85%): open crumb, sticky dough that needs experience. Used for: ciabatta, sourdough boule, artisan styles.
• Above 85%: very wet, needs lamination + specialized technique. Used for: some no-knead breads, slabs.

The formula expressed concretely

For 500g flour at 70% hydration: - 500g × 0.70 = 350g water - Plus 10g salt (~2% of flour weight) - Plus 5g instant yeast (~1% of flour weight) or 100g active sourdough starter

For 500g flour at 75% hydration: - 500g × 0.75 = 375g water - Adjust salt + leavener proportionally

Why salt is also expressed as % of flour weight

In baker's percentage, EVERYTHING is calculated as % of flour weight: - Water: 60-85% (varies by bread type) - Salt: 1.8-2.2% (standard) - Yeast: 1-1.5% (depending on rise speed) - Sugar: 2-10% (if using) - Butter/oil: 5-30% (if using)

This makes recipes scalable + comparable across flour types.

Variables that change required water

Flour type: - White all-purpose: standard 65-70% - Bread flour: similar to AP, maybe +2-3% - Whole wheat: +5-10% (bran absorbs water) - Rye: +10-15% (different starch structure) - Spelt: -5% (lower gluten = less water tolerance) - Tipo 00 (Italian): standard 60-65%

Environment: - Humid kitchen (60%+ humidity): -3-5% water (flour absorbs ambient moisture) - Dry kitchen (30%- humidity): +3-5% water (flour is dry) - Altitude above 3000ft: +5% water (faster evaporation)

Flour age: - Fresh-milled flour: -3-5% water (still moist) - Standard supermarket flour: canonical - Old/stale flour: +5% water (drier)

The autolyse technique (separate water + flour for 30 min)

For high-hydration doughs (70%+): 1. Mix only flour + water (not salt, not yeast) 2. Let rest 30 minutes - 4 hours 3. THEN add salt + yeast/starter 4. Gluten begins developing without mechanical action 5. Dough becomes more pliable + easier to handle

This is a fundamental technique for managing high-hydration doughs. Reduces kneading effort.

Common rookie mistakes

• Adding flour to fix sticky dough: changes hydration percentage + makes bread denser. Use bench flour for handling but don't incorporate into dough.
• Substituting whole wheat 1:1 for white: whole wheat needs +5-10% more water. Recipe will be too dry as written.
• Using cups instead of weight: 25%+ variability ruins consistency. Always weigh.
• Inconsistent water temperature: affects fermentation speed but not final hydration ratio. Use lukewarm (85-95°F) for standard bread.

Cross-reference: see /pages/how-to-convert/cups-to-grams-flour for flour weight conversions + /pages/how-long-does/sourdough-rise for sourdough timing + /pages/how-long-does/dough-rise for general dough rise.