Master Your Bakes with a Sour Dough Calculator — Quickly convert hydration, scale starter and flour, and predict fermentation times so every loaf comes out consistent and flavorful; whether you’re a beginner or an artisan, this must-have sourdough tool removes guesswork and saves time.

Sour Dough Calculator

Fast, reliable sourdough calculator for hydration, baker’s percentage, starter feeding and recipe scaling.

What this sour dough calculator does

This tool helps you convert any sourdough recipe using baker’s math: compute hydration, adjust flour and water weights, calculate required starter (levain) and preferment, scale total dough weight, and plan feedings for your sourdough starter.

Key features and terms

Hydration calculation — determine dough hydration percentage from water and flour.
Baker’s percentage — express ingredient ratios relative to total flour for consistent scaling.
Starter and levain amounts — calculate how much mature starter to build or discard and refresh for a given preferment.
Scaling tool — change batch size or target dough weight and get precise ingredient weights.
Preferment and autolyse — plan preferment build times and autolyse water-to-flour ratios.
Bulk fermentation and proofing guidance — adjust timings based on starter maturity and ambient temperature.
Ingredient conversion — convert between grams, ounces, and cups for different flours and add-ins.

How to use

Enter total flour weight or desired final dough weight.
Set target hydration percentage (e.g., 65% for a medium crumb, 75%+ for open crumb).
Choose starter ratio (e.g., 20% preferment as mature starter at 100% hydration) and specify starter hydration.
Apply baker’s percentage to calculate salt, hydration adjustments, and optional inclusions like seeds, oil or sugar.
Scale recipe up or down; the calculator updates ingredient weights and feeding schedule for your sourdough starter.

Practical examples

Example: For 1000 g total flour at 70% hydration with 20% starter (100% hydration) and 2% salt, the calculator outputs exact grams for water, starter, and salt, plus amounts for preferment and discard management. Use the convert feature to see cup/ounce equivalents if needed.

Tips for best results

Measure ingredients by weight (grams) for accuracy.
Adjust hydration to account for whole grain flours or add-ins that absorb more water.
Consider starter maturity and temperature when planning bulk fermentation and proofing times.
Use autolyse to improve gluten development before mixing in salt and starter.
Refresh your starter with regular feeds to maintain a stable culture for predictable rise.

Related resources

Learn about baker’s percentages, building a levain, preferment techniques, scoring, bench rest, shaping, and oven spring to make the most of this sour dough calculator. For conversion accuracy, consult flour-specific absorption rates and adjust hydration accordingly.

What is a sourdough calculator and how does it help a baker

A sourdough calculator is a tool—either an app, spreadsheet, or paper formula—that helps a baker calculate ingredient weights, baker’s percentages and hydration level for a sourdough bread recipe. It converts recipes between cups and grams, scales a loaf to a desired total dough weight, and shows how each ingredient relates to total flour. Using a sourdough calculator, home bakers and pros can plan fermentation times, adjust the amount of starter or levain, and achieve consistent crumb, crust and flavor.

Calculator for the home baker: using baker’s math and baker’s percentages

For the home baker, the simple sourdough calculator applies baker’s math: express each ingredient as a percentage of total flour. Flour is 100%, water is hydration percentage, salt and starter are shown as percentages too. This makes it easy to scale recipes, convert grams to cups or vice versa, and compare hydration levels between recipes. A baker’s percentages approach helps determine how much starter you need, how much salt to add, and the exact weight of flour and water to mix.

Why a hydration calculator simplifies sourdough and recipe scaling

A hydration calculator focuses on the ratio of water to flour — the hydration level — which dictates dough behavior. By entering total flour and desired hydration, the tool returns grams of water needed and suggests adjustments for different flours or ambient conditions. This simplifies recipe scaling and reduces the guesswork when converting formulas for different loaf sizes or baker’s percentages.

How do I calculate hydration and baker’s percentages?

How to calculate hydration level using flour and water weight

Hydration is calculated by dividing the weight of water by the weight of total flour and multiplying by 100 to get a percentage. Example: 700 g water ÷ 1000 g flour = 0.7 → 70% hydration. A hydration calculator automates this math and can show how changing g of water alters dough consistency, helping the baker decide whether to increase mix time, autolyse length, or adjust flour type for better handling.

Baker’s percentages: total flour, starter, salt and ratio explained

Baker’s percentages set total flour at 100% and express every other ingredient relative to that flour weight. If salt is 2% and you use 1000 g total flour, add 20 g salt. Starter is shown as a percentage of flour (for example 20% starter equals 200 g starter for 1000 g flour), but remember starter itself contains flour and water and should be counted in total flour and total water calculations when using baker’s math. The sourdough calculator clarifies these relationships and outputs correct ingredient weights for the recipe.

Simple sourdough calculator math for beginners

Beginners can use a simple formula: decide total flour weight, choose hydration level, choose starter and salt percentages, then calculate weights. Example steps: choose 500 g total flour (100%), pick 65% hydration → 325 g water, choose 20% starter → 100 g starter (included in flour and water totals depending on method), choose 2% salt → 10 g salt. A basic bread calculator or hydration calculator app will do these calculations for you and adjust automatically if you change any input.

How much starter should I use and how to adjust it?

Calculate amount of starter by percentage and weight

To calculate starter, decide on the percentage of total flour you want as active starter (commonly 10–30% for many sourdough recipes) and multiply by the total flour weight. For a 1000 g flour base at 20% starter, you need 200 g starter. If your starter is 100% hydration (equal parts flour and water), account for its flour and water contributions in your total flour and water calculations to keep baker’s percentages accurate.

Adjust starter ratio for faster or slower fermentation

Adjusting the amount of starter changes fermentation speed: more starter accelerates bulk fermentation and shortens proof time; less starter slows fermentation and increases flavor development and sourness. Use the calculator to increase or decrease starter percentage and recalculate hydration and total dough weight. Also consider ambient temperature — a warmer kitchen may require less starter or shorter fermentation to avoid overproofing.

Levain vs direct starter: when to change your calculation

Levain (prepared preferment) is often calculated separately from direct starter because you build it with additional flour and water. When using levain, include its flour and water in the sourdough calculator inputs so baker’s percentages remain correct. If switching between direct inoculation and levain, adjust your calculations for the amount of active culture and the additional fermentation time required.

How to convert recipes and scale loaves with a bread calculator?

Convert cups to grams: measurement and weight conversion tips

Converting cups to grams eliminates volume imprecision. Different flours have different densities, so a kitchen scale is the most accurate tool. Use standard conversions or a conversion feature in a bread calculator: for example, 1 cup all-purpose flour ≈ 120–125 g, while whole grain flours weigh more. A reliable calculator for the home baker will include these conversion factors and let you input ingredients in cups or grams and output precise weights.

Scale recipe for multiple loaves using a bread calculator

A bread calculator makes scaling easy: enter the original recipe or baker’s percentages, set the desired number of loaves or total dough weight, and the tool recalculates each ingredient’s weight. It can also distribute dough into equal loaves by weight and provide guidance on ferment and bake adjustments for larger batches.

Using an app or manual calculation to maintain hydration and total flour

Whether you use an app or manual calculation, keep total flour and hydration consistent. When you scale, double-check that salt and starter percentages scale proportionally. A smartphone app or spreadsheet reduces math errors and helps the home baker maintain consistent results across batches, preserving hydration level, flavor and texture.

What are common problems and how to troubleshoot hydration issues?

Dough too wet or too dry: how to adjust hydration and mix technique

If dough is too wet and sticky, reduce hydration or increase flour gradually during mixing and use stronger mixing or longer folds to develop gluten. If dough is too dry and stiff, add small increments of water (g of water at a time) and reassess. A hydration calculator can show how small changes affect overall baker’s percentages and total dough weight so you can make precise adjustments.

Impact of flour type and ambient temperature on hydration and fermentation

Whole grain and freshly milled flours absorb more water than refined flours, so they often require a higher hydration level. Warmer kitchens speed up fermentation, while colder environments slow it; both factors may mean you need to adjust starter amount, fermentation time, or hydration level. Use the sourdough calculator to tweak the formula and predict how changes will affect fermentation and crumb.

Proof, ferment, and bake adjustments when changing baker’s percentages

Changing baker’s percentages alters dough behavior: higher hydration yields more open crumb but requires gentler handling and longer proof times; more starter shortens bulk fermentation; more salt slows fermentation and strengthens dough. When you adjust percentages, recalculate proof and bake times and consider retarding in the fridge for flavor control. A calculator helps you model these changes so you can plan the bake accordingly.

Which tools or apps make a perfect sourdough calculator for the home baker?

Features to look for in a hydration calculator and bread calculator app

Look for features like baker’s percentages display, hydration calculator, levain and starter inputs, cup-to-gram conversion, ability to set desired total dough weight, and options to include salt and add-ins. An app that shows the breakdown of flour and water contributed by starter, suggests fermentation times based on starter percentage and temperature, and lets you save formulas makes the perfect sourdough calculator for consistent results.

Best calculator tools for beginners: simple sourdough calculator and conversion

Beginners benefit from a simple sourdough calculator that focuses on core functions: choose flour weight, hydration level, starter and salt percentages, then output grams for each ingredient. Look for apps or web calculators labeled “simple sourdough calculator” or “sourdough bread calculator” that provide clear step-by-step calculations and explanations of baker’s percentages and hydration level.

How a kitchen scale and app together improve consistency and results

A kitchen scale combined with a good calculator app brings precision to your sourdough baking. Weighing ingredients in grams eliminates cup variation and ensures your baker’s percentages are accurate. Use the app to calculate ingredient weights and hydration, then follow the formula on the scale to mix, ferment and bake a more consistent, perfect sourdough loaf every time.