If you've ventured into the world of sourdough baking, sooner or later you will encounter the term hydration. So what exactly does it mean and how does it affect your sourdough baking?


Hydration is the ratio of water to flour in a sourdough starter. You can maintain or adjust the hydration level with each feeding based on the ratio of water to flour you feed your starter.

Though we recommend maintaining your sourdough starter at a hydration level of 100%, you can technically maintain your sourdough starter at other levels depending on the baked good you want to make.

Different recipes may suggest different hydration levels because it will ultimately impact your final sourdough baked good.

  • A lower hydration (under 100%), meaning more flour and less water, is often used to create a thicker dough and stiffer baked good.
  • higher hydration (over 100%), meaning less flour and more water, is more watery and can contribute to a wetter, stickier dough.

How to Achieve 100% Starter Hydration

Feeding by Weight

Feeding by weight, 100% hydration would mean feeding equal weights of starter, flour, and water.

Feeding by Volume

If you feed 1/2 cup of starter with 1 cup flour and 1/2 cup water, the starter will be at 100% hydration. If you feed your 1/2 cup of starter with 1 cup flour and 1/4 cup water, the starter will be at 50% hydration.

Using Thicker Starter

Why Use a Thicker Starter with Lower Hydration

For recipes that call only for sourdough starter and no additional flour, sometimes a thicker starter is beneficial. This rule is particularly true for gluten-free sourdough pancakes and baked goods that lack gluten, as a thicker batter holds together better in cooking and flipping.

Learn more about gluten-free sourdough baking.

How to Create a Thicker Starter

To that end, if pancakes are a regular part of the morning meal, it may be helpful to maintain a slightly thicker starter. Feeding a starter 1 cup flour and 6 tablespoons water, or 75% hydration, is a good place to start. From there, determine if more or less water at a feeding is desirable.

Keep in mind that most recipes are developed with a 100% hydration sourdough starter, and so any deviation from that, especially for those recipes that are not stand-alone starter recipes, will produce a different final product.

Recipes for a Thicker Starter

If you find yourself with a thicker starter, maintained at a lower hydration level there are lots of ways to use it. Try one of these recipes that suggest a lower hydration level.

Need a Sourdough Starter?

There are countless recipes online for creating a sourdough starter from scratch. While this only requires some basic equipment and ingredients, it also requires patience and unfortunately, isn't always reliable.

There are ways to obtain an established sourdough starter that offer a bit more reliability. Learn more about which starter might be right for you and happy baking!