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Sourdough planner

Sourdough Calculator

Last reviewed: April 2026
Built and maintained by · Last updated April 2026

Choose a recipe, set your kitchen temperature, and get a realistic formula and bake plan.

Simple mode is the default. Advanced mode adds formula tuning, flour blend control, starter hydration, DDT, and custom recipes without losing your current bake.

Jump to How-to Guide ↓
Recipe Base

Select your recipe and yield

Start by selecting a recipe base, then scale the yield to your desired loaf size.

Understand the why

Recipe

Grouped preset library plus any saved custom recipes.

Yield

Extra Ingredients (Baker's %)

Add mix-ins like cheese, olives, or seeds. Scales automatically with total flour.

Starter readiness

More starter options

Kitchen temperature

Temperature is the biggest driver of fermentation speed.

Schedule

Using defaults

Switch to Advanced mode at any time to adjust formula, flour blend, starter hydration, or dough temperature inputs.

Core results

Formula and bake outlook

Recipe summary

Current recipe

Bake confidence

Formula Analysis

Advanced controls

Formula, fermentation, and custom recipes

Switch to Advanced mode to reveal the expert controls below. Your current bake will stay intact.

Export and share

Take the plan with you

Important Disclaimer: The information provided by the Sourdough Calculator is for educational purposes only and doesn't constitute professional advice. Always consult with a qualified expert for accurate guidance tailored to your specific needs.

How to Calculate Sourdough Starter

The Sourdough Calculator is a useful tool for anyone looking to embark on the delightful journey of sourdough baking. This guide will walk you through the steps and calculations needed to create your very own sourdough starter at home.

Data Insights

Understanding the science behind sourdough starter is crucial for anyone looking to bake this delicious bread. The key to a successful sourdough starter is the right balance of bacteria and yeast. The Sourdough Calculator helps you understand how to achieve this balance by providing you with the necessary information on the amount of flour and water required.

Real-World Applications

The Sourdough Calculator can be applied in various real-world scenarios. For example, if you are planning a large gathering and want to ensure you have enough sourdough bread for everyone, the calculator can help you determine the number of sourdough starters you need. Additionally, if you are a baker looking to experiment with different recipes, the calculator can help you understand how to adjust the amount of flour and water needed for each recipe.

Common Mistakes

One of the most common mistakes when making a sourdough starter isn't following the correct ratio of flour to water. If you use too much flour, your starter may not rise properly. If you use too much water, your starter may be too wet and not activate properly. The Sourdough Calculator helps you avoid these mistakes by providing you with the correct ratio of flour to water for your starter.

Examples

Example 1: Making a Sourdough Starter

Let's say you want to make a sourdough starter using 100 grams of flour. According to the Sourdough Calculator, you will need to use 100 grams of water. Mix the flour and water together and cover with a damp cloth. Place the starter in a warm place and let it sit for 24 hours. After 24 hours, your starter should have doubled in size and be ready to use.

Example 2: Adjusting the Amount of Flour and Water

Let's say you want to make a sourdough starter using 200 grams of flour. According to the Sourdough Calculator, you will need to use 200 grams of water. Mix the flour and water together and cover with a damp cloth. Place the starter in a warm place and let it sit for 24 hours. After 24 hours, your starter should have doubled in size and be ready to use.

Example 3: Troubleshooting a Sourdough Starter

Let's say your sourdough starter isn't rising properly. According to the Sourdough Calculator, this could be due to using too much flour. Try using less flour and more water. Mix the flour and water together and cover with a damp cloth. Place the starter in a warm place and let it sit for 24 hours. After 24 hours, your starter should have doubled in size and be ready to use.

FAQs

Q1: How long does it take to make a sourdough starter?

A1: It typically takes 24-48 hours for a sourdough starter to double in size. However, this can vary depending on the temperature and humidity of your environment.

Q2: How often should I feed my sourdough starter?

A2: It's recommended to feed your sourdough starter every 12 hours. Mix 100 grams of flour and water and add it to your starter. Cover with a damp cloth and place in a warm place.

Q3: How do I know if my sourdough starter is active?

A3: A active sourdough starter will double in size within 24 hours. If it does not, it may be inactive and needs to be fed more frequently.

How to use this sourdough planner

  1. Start with the recipe and yield. In Simple mode, pick the loaf you want, the number of loaves, and the size per loaf.
  2. Tell the planner about your starter and kitchen. Starter readiness and temperature are the two biggest variables that change the clock.
  3. Choose the schedule direction. You can start now or work backward from mix time, bake time, or when the loaf should be cool enough to eat.
  4. Read the output in order. Use the formula summary first, then the levain plan, then the timeline, then the method cards.
  5. Use the dough to confirm the clock. The planner is deterministic, but the timings are still estimates. The sensory cues are there because sourdough still lives in your actual kitchen.

What changed in this refactor

The calculator now opens in a guided Simple mode that keeps baker's percentages and DDT out of the way until you want them. Advanced mode still exposes formula tuning, flour blend control, starter hydration, dough temperature planning, and local custom recipes.

What the timeline is doing

The timeline combines levain build timing, fermentation estimates, shaping steps, cold proofing, and oven phases. Variable stages such as levain maturity and bulk fermentation still show sensory cues and timing windows so the planner does not pretend to be more precise than the dough really is.

Frequently Asked Questions

A1: It typically takes 24-48 hours for a sourdough starter to double in size. However, this can vary depending on the temperature and humidity of your environment.
A2: It is recommended to feed your sourdough starter every 12 hours. Mix 100 grams of flour and water and add it to your starter. Cover with a damp cloth and place in a warm place.
A3: A active sourdough starter will double in size within 24 hours. If it does not, it may be inactive and needs to be fed more frequently.