Poolish is a liquid preferment originating from Poland, made with equal weights of flour and water (100% hydration) and a tiny amount of commercial yeast (0.08-0.2%). It ferments for 12-16 hours at room temperature, developing a nutty, slightly tangy flavor and improved dough strength. Poolish is ideal for baguettes, ciabatta, and other artisan breads where an open crumb and crispy crust are desired.

Biga is an Italian-style stiff preferment with lower hydration (typically 50-55%). It uses 0.2-0.5% yeast relative to its flour and ferments for 16-24 hours at cool room temperature. The stiffer texture slows fermentation, producing complex, slightly acidic flavors. Biga is traditional in Italian breads like Pane Toscano, ciabatta (some versions), and pizza dough, contributing excellent keeping quality and a chewy, irregular crumb.

Hydration: Poolish is 100% (liquid batter); Biga is 50-55% (stiff dough).
Yeast amount: Poolish uses less yeast (0.08-0.2%) due to faster fermentation in liquid; Biga needs slightly more (0.2-0.5%).
Fermentation time: Poolish 12-16h; Biga 16-24h.
Flavor profile: Poolish yields mild, nutty, sweet notes; Biga develops deeper, more complex acidity.
Best for: Poolish suits French-style breads; Biga excels in Italian breads and pizza.

For a standard 12-16 hour room-temperature fermentation, use 0.1% instant yeast relative to the poolish flour weight. For example, if your poolish contains 300g flour, use 0.3g yeast (about 1/10 teaspoon). In warmer conditions, reduce to 0.05-0.08%; in cooler conditions, increase to 0.15-0.2%. The poolish is ready when bubbly, domed on top, and just beginning to recede in the center.

Biga typically requires 0.2-0.5% instant yeast based on the biga flour weight. For a biga with 350g flour, use 0.7-1.75g yeast. The stiffer dough and cooler fermentation (often 16-24h) require slightly more yeast than poolish. Adjust based on ambient temperature: cooler = more yeast, warmer = less. A mature biga should smell pleasantly acidic and show a network of small holes when broken open.

Most artisan recipes use 20-40% of total flour in the preferment. A 30% preferment is a common sweet spot: enough to develop significant flavor and dough strength without making the final dough unmanageable. Higher percentages (40-50%) yield more intense flavor but require careful handling as the dough may ferment faster. Lower percentages (15-20%) provide subtle improvement and are good for beginners or when time is limited.

Poolish: Look for a bubbly surface with small and large bubbles, a domed top that's just starting to flatten or slightly recede in the center, and a pleasant yeasty-nutty aroma. It should jiggle when the bowl is shaken.
Biga: The stiff dough should have visibly expanded, feel airy when broken apart, reveal a honeycomb-like internal structure, and smell mildly acidic and complex. Both are best used at their peak – don't wait until they fully collapse.

Yes, but you must adjust the final dough water to maintain your target overall hydration. If swapping poolish (100% hydration) for biga (55% hydration) using the same flour weight, the poolish contributes more water to the final dough, so reduce the added water accordingly. Our calculator handles this automatically. Note that the flavor profile will also change: poolish gives milder notes; biga adds more complexity and acidity.

Baker's percentage expresses all ingredients as a percentage of total flour weight (which is always 100%). This system makes recipes scalable and easy to compare. For example, 68% hydration means water equals 68% of total flour weight. Salt is typically 1.8-2.2%. Our calculator uses baker's percentage throughout, so you can scale any recipe up or down simply by changing the total flour weight.

This often happens when the preferment hydration and total hydration settings conflict. If your preferment has high hydration (like 100% poolish) but your total hydration is low (e.g., 60%), the final dough water may become very low or even negative. Our calculator warns you when this occurs. Adjust by either lowering preferment hydration, reducing preferment flour percentage, or increasing total hydration. A negative final dough water value means your parameters are incompatible.

Our calculator uses these conversions: 1 cup all-purpose flour ≈ 125g, 1 oz ≈ 28.35g. For water: 1 cup ≈ 237g, 1 oz ≈ 29.57g. Note that cups are inherently less precise for flour (scooping method can vary ±15%). For consistent results, we strongly recommend using a digital kitchen scale and working in grams. Professional bakers exclusively use weight measurements for accuracy.