Recipe checker
Include starter flour and water in true hydration.
Enter the written dough and starter formula and review component totals.
Can reproduce total hydration, salt percentage, and prefermented flour.
Sourdough Hydration Calculator
Calculate true sourdough hydration, salt percentage, prefermented flour, starter contribution, loaf weight, and water adjustments for target hydration.
Use this result well
- Inputs that matter
- Added flour/water, starter mass and hydration, salt mass, target hydration, and whole loaf count
- Output to expect
- Starter flour/water, total flour/water, hydration, salt and prefermented-flour percentages, total/portion weight, and a pre-mix water-or-flour target adjustment
- How it works
- Split starter into flour and water, include both in baker’s percentages, then add water for a higher target or flour for a lower target
- Use the target adjustment before mixing; the tool never claims already mixed water can be removed.
- Baker’s-percentage arithmetic does not predict handling, fermentation time, crumb, loaf volume, food safety, or recipe suitability.
Choose your path
Built around the job you need to finish
Audit a sourdough formula using complete baker’s arithmetic and calculate a physically possible pre-mix target adjustment.
Baker planning a target
Adjust hydration before mixing.
Compare current and target hydration.
Adds water for a higher target or flour for a lower target—never removes mixed-in water.
Batch divider
Plan equal dough portions.
Enter a whole loaf count and inspect total and per-loaf mass.
Uses weight arithmetic without treating it as a fermentation or crumb forecast.
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Projects using Sourdough Hydration Calculator
This tool is part of these guided projects. Each project provides step-by-step instructions with checklists and all the tools you need in one place.
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Reference & details
How it works
Updated July 2026
How it works
Updated July 2026Starter is split into flour and water
Starter flour and starter water are derived from starter weight and starter hydration, then added to the main flour and water totals.
starter flour = starter / (1 + starter hydration / 100)True hydration
Hydration is total water divided by total flour. This is more accurate than comparing only the added flour and added water.
Recipe Scaling
The Sourdough Hydration Calculator scales ingredient quantities linearly by serving count or batch size. Non-linear items (yeast, salt, leavening) may use sub-linear scaling factors.
Scaled Amount = Base × (New Servings ÷ Original Servings)Updated: July 2026
Example Scenarios
Enter the current formula and target hydration before mixing to see how much water or flour would produce that target.
Use dough weight and loaf count to portion dough before shaping.
Compare total flour, total water, salt percentage, and prefermented flour before committing ingredients to a mix.
Common Mistakes to Avoid
Common Mistakes to Avoid
Ignoring starter hydration
A 100% hydration starter contributes equal flour and water, which changes the real dough hydration.
Trying to remove water from mixed dough
Use the target adjustment while planning. A lower target is reached by adding flour to the formula, not by pretending mixed-in water can be removed.
FAQ
The calculator does not choose a handling target. Flour absorption, grain type, fermentation, temperature, inclusions, and technique all affect how a given percentage behaves.
Enter the salt weight required by your recipe and review its baker's percentage. Taste, process, dietary needs, and the source recipe should guide the target.
Here it means starter flour divided by total flour. It describes formula composition; it does not by itself predict fermentation time.
It calculates starter flour and water, total hydration, salt percentage, prefermented flour, total dough weight, loaf portions, and a pre-mix target adjustment.
The baker's-percentage arithmetic is deterministic from the entered weights. It cannot predict fermentation, handling, loaf volume, or crumb.
About Sourdough Hydration Calculator
Analyze a sourdough formula the way bakers do: include the flour and water inside the starter, then calculate hydration, salt percentage, inoculation, and dough weight.