Baker's Percentage Calculator (Bread Hydration)

Baker's Percentage Guide

What Baker's Percentages Are?

Baker's percentage is the standard way professional and serious home bakers describe bread recipes. The convention: flour always = 100% (the reference). All other ingredients expressed as % of flour weight. Why this matters: scales perfectly. Want twice as much bread? Double everything proportionally. Compare recipes easily — a '75% hydration' bread is wetter than a '60% hydration' bread regardless of absolute weights. Spot mistakes — recipes with 'unusual' percentages stand out immediately. Adjusting a recipe up or down in batch size is simple, since every ingredient scales by the same proportion relative to the flour.

What should I know about Hydration Ranges by Bread Type?

Low hydration (55-65%): bagels (50-55%) — chewy, dense. Pretzels. Some pizza dough. Easier to handle, tighter crumb. Medium hydration (65-72%): tin loaves. Pita. Most everyday breads. Balance of handling and crumb structure. Higher hydration (72-80%): baguettes. Sourdough country breads. Ciabatta. More open crumb, blistered crust. Requires skill to handle. Very high hydration (80-100%): focaccia. Roman al taglio pizza. Ciabatta extreme. Liquid texture — uses bench scrapers, can't really 'knead'

What's the key thing to understand about Sourdough Starter Math?

When using sourdough starter, you need to account for the flour and water in the starter itself. Typical starter is 100% hydration (equal flour and water by weight). 100g of 100% hydration starter = 50g flour + 50g water. Calculation adjustment: target total flour 1000g, 75% hydration. Adding 200g starter (= 100g flour + 100g water). Effectively your dough already has 100g flour + 100g water before adding more. To hit final 1000g flour total: add 900g more flour, since the starter itself contributes the remaining 100g. To hit 75% hydration on 1000g total flour: add 750g water minus whatever water the starter already contributes.

What should I know about Practical Recipe Examples?

Classic French baguette: 100% flour. 65% water. 2% salt. 1% fresh yeast (0.4% instant dry). 18-20 hour cold ferment. Tartine country loaf (Chad Robertson): 100% flour (90% strong white, 10% wholemeal). 75% water. 2% salt. 15-20% sourdough starter. 12-hour bulk ferment, 4-hour proof. Focaccia: 100% flour. 80% water. 2% salt. 1% instant yeast. 5% olive oil. Plus oil on top before baking. Sandwich loaf: 100% flour. 65% water. 2% salt. 1% instant yeast. 5% milk powder. 8% sugar. 5% butter. Soft, sweet enriched dough typical of a supermarket-style sandwich loaf.

What should I know about Why Flour Is Always 100%?

Baker's percentage is a convention, not a literal statement that flour makes up 100% of the dough's weight — it's a system where the total flour weight (including any flour contributed by a starter or preferment) is set as the 100% baseline reference, and every other ingredient's weight is expressed as a percentage of that flour weight, regardless of the recipe's actual total size. This is exactly why bp_flour_weight is the one input this calculator treats as the fixed reference point that every other output (bp_water_g, bp_salt_g, bp_yeast_g, and the optional ingredients) is calculated from. The real power of this system is that it lets a baker scale any recipe to any batch size they want while perfectly preserving the ratios that define that particular bread's character — a baker can take the exact same set of percentages used for a single home loaf and apply them to a ten-loaf commercial batch, and the dough will behave identically in terms of hydration, saltiness, and fermentation characteristics, just at a different total weight.

What should I know about Enriched Dough Percentages (Oil, Sugar, Eggs)?

Adding significant fat and sugar to a dough — as in brioche, challah, or milk bread, reflected in this calculator's optional bp_olive_oil_pct and bp_sugar_pct inputs — changes dough behavior in ways that pure lean bread percentages don't capture. Sugar is hygroscopic, meaning it competes with flour for available water, which can make an enriched dough feel firmer than its stated hydration would suggest in a lean dough, and at high concentrations sugar can also slow yeast activity somewhat, since it creates a more concentrated environment that yeast has to work harder against (though in strictly moderate amounts, a little sugar actually helps feed the yeast more than it hinders it). Fat, meanwhile, coats gluten strands and weakens the gluten network's structure, generally producing a softer, more tender, closer crumb rather than the open, chewy structure of a lean bread, and can require slightly longer or gentler mixing and proofing to develop properly. Recipes with egg or dairy added also effectively contribute additional water and fat beyond what's captured in a simple flour/water/salt/yeast percentage breakdown, which is why well-developed enriched dough formulas typically track egg and dairy contributions as their own percentages alongside this calculator's optional ingredient fields, rather than folding them silently into the water percentage.

What do I need to know about Salt Percentage and Its Effect on Fermentation?

Salt in bread dough does more than season the final loaf — it directly affects fermentation speed and gluten structure, which is why baker's percentage for salt (typically 1.8-2.2% of flour weight in most bread recipes) is kept within a fairly narrow, well-tested range rather than adjusted freely to taste. Salt slows yeast activity by drawing water out of yeast cells through osmosis, meaning a dough with more salt than the recipe specifies will ferment more slowly, while a dough with less salt (or none) ferments noticeably faster but produces weaker, stickier gluten structure, since salt also helps tighten and strengthen the gluten network by affecting how the proteins interact with water. This is why professional bakers are generally cautious about adjusting salt percentage purely for taste without considering its effect on timing — a lower-salt dough left to proof for the standard time, expecting slower activity like a higher-salt dough, can easily over-proof. Salt-free bread, sometimes made for health reasons, needs a correspondingly adjusted (usually faster) proofing schedule and often benefits from slightly reduced yeast to compensate for the faster-than-normal fermentation that removing salt's moderating effect produces, rather than simply following a standard recipe's timing with the salt omitted.

Worked Example: Converting a Home Recipe to Baker's Percentages

A home recipe listing 600g flour, 420g water, 12g salt and 8g instant yeast converts to baker's percentages by dividing every ingredient by the flour weight and multiplying by 100. Water: 420 / 600 x 100 = 70% hydration. Salt: 12 / 600 x 100 = 2%. Yeast: 8 / 600 x 100 ≈ 1.3%. Expressed this way, the recipe (70% hydration, 2% salt, 1.3% yeast) can be instantly compared with other recipes regardless of batch size, and scaled to any flour weight by simply reversing the calculation: a baker wanting the same recipe at 1kg flour would use 700g water, 20g salt and 13g yeast.

Accounting for Pre-Fermented Flour in the Total Formula

When a recipe includes a preferment such as a poolish, biga, or sourdough starter, the flour and water already inside that preferment are part of the dough's total flour and water, not an addition on top of it, which is a common point of confusion when converting a recipe to baker's percentages. For example, a dough with 400g flour mixed fresh plus a poolish built from 100g flour and 100g water contains 500g total flour, not 400g, and the baker's percentages for hydration, salt and yeast should be calculated against that full 500g, not just the freshly added portion. Professional formulas sometimes express this as "total formula" percentages (covering every gram of flour and water in the final dough, preferment included) specifically to avoid this miscalculation, since getting it wrong by even a modest margin changes the real hydration and salt percentage of the finished dough more than it might first appear.

Why Percentages Alone Don't Guarantee an Identical Loaf

Two doughs with identical baker's percentages for hydration, salt and yeast can still behave differently in practice, because baker's percentages don't capture flour protein content, mixing method, ambient temperature, or fermentation time, all of which also shape the final dough's handling and the finished loaf's texture. A 70% hydration dough made with a strong bread flour behaves noticeably differently from the same percentage made with a softer, lower-protein flour, since the flour's own water-absorbing and gluten-forming capacity varies by type. Baker's percentages are best understood as a precise way to describe and scale a formula's ratios, not as a complete substitute for also specifying flour type, fermentation schedule and technique.