Sourdough Hydration Calculator

Calculate the precise baker’s percentage and hydration for your sourdough bread recipes.

Dough Composition Visualization

Formula: Total Hydration = (Water in Recipe + Water in Starter) / (Flour in Recipe + Flour in Starter) × 100.

Using a sourdough hydration calculator is one of the most significant steps a home baker can take to move from “good” bread to “professional” bread. Hydration refers to the weight ratio of water to flour in your dough, and it is the single most important variable in determining the crumb structure, crust texture, and overall handling of the dough.

Whether you are aiming for a tight, sandwich-style loaf or an open, airy crumb with large alveoli, the sourdough hydration calculator provides the mathematical precision required to replicate results every single time. It accounts for the water and flour already present in your sourdough starter, ensuring your final percentages are accurate.

Sourdough Hydration Calculator Formula and Mathematical Explanation

The math behind bread baking is often referred to as “Baker’s Percentage.” Unlike standard percentages where all ingredients sum to 100%, in baker’s math, the total flour weight always represents 100%, and every other ingredient is measured relative to that flour weight.

To calculate the true hydration using a sourdough hydration calculator, we must include the flour and water from the starter:

1. Step 1: Calculate Flour in Starter = Starter Weight / (1 + (Starter Hydration / 100))
2. Step 2: Calculate Water in Starter = Starter Weight – Flour in Starter
3. Step 3: Total Flour = Added Flour + Flour in Starter
4. Step 4: Total Water = Added Water + Water in Starter
5. Step 5: Hydration % = (Total Water / Total Flour) * 100

Variable	Meaning	Unit	Typical Range
Flour Weight	The dry flour added to the mixing bowl	Grams (g)	250g – 1000g
Water Weight	The liquid water added to the mixing bowl	Grams (g)	150g – 850g
Starter Weight	The amount of fermented levain used	Grams (g)	50g – 200g
Starter Hydration	The ratio of water to flour in the starter	Percentage (%)	100% (equal parts)
Salt	The sodium content for flavor and strength	Grams (g)	1.8% – 2.2%

Practical Examples (Real-World Use Cases)

Example 1: The Standard Country Loaf

If you input 500g flour, 350g water, and 100g of 100% hydration starter into the sourdough hydration calculator, the total flour becomes 550g (500 + 50) and total water becomes 400g (350 + 50). This results in a 72.7% hydration loaf. This range is perfect for beginners as it is easy to shape but still produces a soft, open crumb.

Example 2: High Hydration Tartine Style

For a more advanced baker using 500g flour, 400g water, and 100g starter, the sourdough hydration calculator will show 81.8% hydration. This dough will be very slack and sticky, requiring advanced folding techniques like the autolyse process to build enough structural strength.

How to Use This Sourdough Hydration Calculator

1. Enter Flour Weight: Start by entering the amount of flour your recipe calls for. Most standard loaves use between 400g and 500g.
2. Enter Water Weight: Add the intended water amount. If you are unsure, start lower; you can always add more during the high hydration dough mixing phase.
3. Adjust Starter: Input your starter weight. Most recipes use 20% of the flour weight (e.g., 100g starter for 500g flour).
4. Check Starter Hydration: If you feed your starter equal weights of flour and water, leave this at 100%.
5. Analyze Results: Look at the “Total Hydration” percentage. High hydration (over 75%) is harder to handle but yields a crispier crust and airier crumb.

Key Factors That Affect Sourdough Hydration Results

• Flour Type: Different flours absorb water differently. High-protein bread flour can handle 80% hydration easily, while All-Purpose flour may turn into soup at the same level.
• Humidity: High ambient humidity means your flour already contains more moisture, effectively increasing the hydration.
• Starter Maturity: A very active, bubbly starter may slightly change the consistency of the dough compared to a “hungry” one.
• Salt Content: While salt doesn’t change hydration math, it tightens gluten. A low-salt dough at high hydration will be much harder to manage.
• Inclusions: Adding seeds, nuts, or olives? Many of these absorb water. You may need to increase the water in your sourdough hydration calculator to compensate.
• Temperature: Warmer dough feels more “liquid” and slack than cold dough, even if the hydration percentage is identical.

Frequently Asked Questions (FAQ)

What is a good hydration for beginners?

For those new to the craft, 65% to 70% is ideal. It provides enough moisture for a good crumb without being overly sticky or difficult to shape.

Does the starter hydration really matter?

Yes. If you use a “stiff” starter (50% hydration) vs. a “liquid” starter (100%), the total water in the recipe changes significantly. The sourdough hydration calculator accounts for this.

Why is my 75% hydration dough stickier than the recipe says?

This is often due to the flour type. If your flour has lower protein content, it cannot absorb as much water, making the dough feel more hydrated than it is.

How do I increase hydration in an existing recipe?

Add water 10 grams at a time during the initial mix. Use the sourdough hydration calculator to track your new target percentage for future consistency.

Does hydration affect fermentation speed?

Generally, yes. Higher hydration doughs tend to ferment faster because yeast and bacteria can move more easily through a more liquid medium.

What is the “Bakers Percentage”?

It is a notation method where all ingredients are expressed as a percentage of the total flour weight. You can learn more in our bakers percentage guide.

Should I include salt in the hydration calculation?

No, hydration only measures the ratio of water to flour. However, salt is calculated as a percentage of the total flour.

What hydration is used for ciabatta?

Ciabatta is a very high hydration dough, often reaching 80% to 90%, which gives it its characteristic large holes.

Related Tools and Internal Resources

• Classic Sourdough Bread Recipe – A foolproof guide for your first loaf.
• Sourdough Starter Maintenance – Learn how to keep your starter healthy and active.
• Bakers Percentage Guide – Deep dive into the math of professional baking.
• High Hydration Dough Tips – Handling techniques for wet doughs.
• Bread Flour vs All Purpose – Understanding protein content and absorption.
• Autolyse Process Benefits – Why you should rest your dough before adding salt.