Reconcile one already-selected sourdough refresh by mass, including source-starter flour and water, actual addition ratio, final hydration, prefermented-flour share, and an optional completed-report comparison.
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A quick decision brief for this specific tool
Inputs that matter
One named sourdough refresh record and basis; responsible reviewer; exact formula/source revision; retained-starter identity and source-composition record; added-flour, added-water, scale, uncertainty/transfer-loss, optional completed-report and downstream-boundary records; one supported mass-balance boundary; already-selected ratio ownership; external raw-flour/final-use boundary; one mass unit; source-starter hydration; scale resolution; either retained starter plus completed flour/water additions or one target final mass plus already-selected starter:flour:water mass parts; optional same-basis completed final mass and refreshed hydration supplied as a pair; and user-owned mass/hydration arithmetic tolerances
Output to expect
Normalized retained starter, flour and water masses; source-starter flour/water decomposition; actual added-mass starter:flour:water ratio; final total mass, total flour and total water; refreshed flour-basis hydration and dough yield; prefermented-flour share; optional completed-report mass/hydration differences inside entered tolerances; explicit source/boundary records; and stable Project outputs that keep culture-health, fermentation-peak, bake-readiness and food-safety flags false
How it works
For completed mode reconcile final mass from the measured retained starter and additions; for target mode allocate the entered final mass in proportion to the already-selected starter:flour:water parts; decompose retained starter as source flour = starter ÷ (1 + source hydration/100) and source water = starter − source flour; then calculate final hydration = total water ÷ total flour ×100, dough yield = 100 + hydration and prefermented flour = source flour ÷ total flour ×100 before any optional same-basis arithmetic comparison
Only one already-selected refresh mass record executes. This Tool does not choose a feed ratio from time, temperature, acidity, culture condition, maintenance goal or bake plan and does not create or diagnose a culture, predict peak/rise/readiness, acidity, microbiome or flavor, or prescribe discard, storage, ingredients or a schedule.
Mass agreement is not food-safety, allergen, contamination, tasting, consumption or final-bake approval. Confirm the exact starter and ingredients, follow current raw-flour handling and allergen controls, inspect the culture externally, and keep recipe, storage and final-use decisions with the responsible process.
Choose your path
Built around the job you need to finish
Reconcile one source-owned sourdough refresh mass record from measured retained starter and additions or from a target total plus already-selected mass parts, while exposing source-starter flour/water composition, actual ratio, final hydration, prefermented-flour share and report agreement without choosing a feed ratio or claiming culture health, timing, readiness, storage, food safety or bake approval.
Maintenance-record reviewer checking a completed refresh
Reconcile the actual retained starter, flour and water masses against one named worksheet without letting a symmetric ratio label hide an asymmetric addition or source-starter composition.
Freeze the jar/batch, formula revision, 100% source hydration, ingredient and scale records; enter 50 g retained starter, 100 g flour and 125 g water; inspect the actual 1:2:2.5 ratio, source decomposition, 120% refreshed hydration and optional same-basis report differences before deliberate retention.
Gets a reproducible mass record and a field-owned mismatch when the report disagrees, while culture condition, contamination, maintenance timing and storage remain with the named external review.
Baker scaling an already-selected levain build
Allocate a chosen final levain mass from recipe-owned starter:flour:water parts in grams or kilograms without the Tool selecting or recommending that ratio.
Select target-total mode, record the responsible formula and already-selected 1:2:2 mass parts, enter 250 g or 0.25 kg final mass and the source-starter hydration, leave completed-addition fields blank, then review 50/100/100 allocation and final composition.
Receives unit-equivalent masses, actual ratio and flour-basis hydration while fermentation schedule, readiness, recipe suitability and final bake decision remain explicitly external.
Instructor or auditor checking hydration and report semantics
Show that retained starter already contains flour and water and that display resolution, arithmetic tolerances and biological variability are different concepts.
Compare 50%, 100% and 125% source-starter hydration records; verify decomposition and prefermented-flour share; trigger partial-report, tolerance, unsupported ratio-selection and food-safety paths; then recover with a complete same-basis report.
Can explain and reproduce the mass equations and every refusal without presenting the simulated exercise as microbiome research, sensory validation, safety testing or user research.
Authoritative checks for this tool
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
Completed mode uses measured retained starter, added flour, and added water. Target mode allocates one chosen final mass from already-selected starter:flour:water parts. Fields from the other mode must stay blank.
Final mass = retained starter + added flour + added water
Include the retained starter's composition
The retained starter already contains flour and water. The recorded source hydration decomposes that mass before final hydration, dough yield, and prefermented-flour share are calculated.
Source flour = starter ÷ (1 + source hydration / 100); final hydration = total water ÷ total flour × 100
Reconcile arithmetic, not biology
An optional completed report must provide both same-basis final mass and refreshed hydration. Entered tolerances compare arithmetic and transcription only; they are not measurement uncertainty, biological variability, readiness, or safety limits.
Difference = completed report value − calculated same-basis value
Updated: August 2026
Example Scenarios
Record 50 g of 100%-hydration source starter, 100 g flour, and 125 g water. The Tool reports 275 g total, an actual 1:2:2.5 addition ratio, and 120% refreshed hydration after including the starter's 25 g flour and 25 g water.
For a responsible formula that already specifies 1:2:2 mass parts and 250 g final mass, target mode allocates 50 g retained starter, 100 g added flour, and 100 g added water without recommending that ratio.
Attach the exact starter, ingredient, scale, source-hydration, formula, and report records. Compare final mass and refreshed hydration inside reviewer-owned tolerances; any culture observation, contamination, storage, recipe, or food-use decision remains external.
Common Mistakes to Avoid
✕
Treating added-water percentage as final hydration
✓
First decompose retained starter into its recorded flour and water, then add the new flour and water. Calculate final hydration from all flour and all water on the same mass basis.
✕
Treating a matching mass record as a culture or safety approval
✓
Retain the result only as arithmetic evidence. A responsible person must still review the actual starter, ingredients, contamination observations, raw-flour and allergen controls, storage, recipe, consumption, and final bake.
FAQ
It reports the actual retained-starter:added-flour:added-water mass ratio. If water differs from flour, the final term differs too; the Tool never relabels 1:2:2.5 as 1:2:2.
Retained starter contributes both flour and water. Its recorded flour-basis hydration determines that split, so it changes final total flour, total water, refreshed hydration, dough yield, and prefermented-flour share.
No. The ratio or masses must come from a responsible recipe, reviewer, or recorded process. This Tool will not infer them from time, temperature, acidity, culture condition, maintenance goals, or a bake plan.
No. Mass arithmetic cannot diagnose culture health or contamination or predict peak, rise, acidity, microbiome, flavor, or bake readiness. Keep observations and decisions in the responsible external process.
No. Flour is a raw food and mass agreement does not approve tasting, consumption, allergens, contamination status, storage, or a finished bake. Follow current ingredient, raw-flour, allergen, cleaning, separation, and final-cooking controls.
About Sourdough Refresh Mass Calculator
Use this Tool after a responsible recipe or reviewer has selected the refresh masses or starter:flour:water parts. It reconciles mass and flour-basis composition only; it does not choose a feeding ratio, diagnose a living culture, predict fermentation, prescribe storage, or approve tasting, consumption, allergens, food safety, or a final bake.
