Sourdough Starter Ratios Explained
Updated Mar 23, 2026
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Sourdough starter feeding ratios are one of the easiest ways to control your baking schedule. This is one of the biggest mindset shifts in sourdough baking.
By adjusting how much flour and water you feed your starter, you can control how quickly it becomes active and when it will be ready to use. Once you understand this, sourdough becomes much more predictable and easy to make.
And don’t worry, it’s not complicated. It’s just a simple way to make your starter work on your schedule instead of the other way around.
Remember back to your 6th grade math class? You know, the one where you learned about ratios and thought you would never use them again? Well, maybe that was just me, but I was proved wrong as soon as I started baking sourdough.
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Table of Contents
- What is a Sourdough Starter Ratio?
- Why Feeding Ratios Matter
- How Temperature Impacts Feeding Ratios
- How Flour Impacts Feeding Ratios
- Choosing the Right Feeding Ratio
- Sourdough Starter Ratio Chart
- Maintaining a Healthy Sourdough Starter Using Ratios
- Ratios in Your Dough
- Amy’s Real Life Ratio Tip
- Frequently Asked Ratio Questions
- What to Do Next
- Popular Sourdough Recipes
What is a Sourdough Starter Ratio?
A sourdough starter ratio compares the amount of starter, flour, and water by weight (not volume).
For example:
- 1:1:1 → equal parts starter, flour, and water
- 1:2:2 → more flour and water than starter
- 1:10:10 → a small amount of starter with a larger feeding
The ratio you use directly affects how quickly your starter will rise and when it will be ready to use.
Why Feeding Ratios Matter
Feeding ratios control how quickly your starter becomes active.
- more starter → faster rise
- less starter → slower rise
This means you can adjust your feeding to match your schedule instead of trying to time your day around your starter.
This flexibility allows you to make your starter ready when you need it, whether you’re baking the same day or planning ahead. A larger amount of starter will speed things up, while a smaller amount of starter with more flour and water will slow things down.
I’ve tested feeding my sourdough starter at many different ratios, and I use all of them depending on what I need. The more starter you carry over compared to the flour and water, the faster your starter will peak. The less starter you carry over, the longer it will take.
This photo shows one of my tests using jars with different feeding ratios.
How Temperature Impacts Feeding Ratios
Temperature plays a big role in how your starter behaves.
- cooler temperatures → slower fermentation
- warmer temperatures → faster fermentation
You can increase the amount of starter in your feeding, but if your environment is cold, it will still take longer to become active. Wild yeast and bacteria thrive in warm conditions, which means temperature directly impacts how quickly your starter rises and peaks.
Feeding ratio and temperature work together. Adjusting both allows you to control when your starter will be ready and make it fit your schedule.
How Flour Impacts Feeding Ratios
The type of flour you use can also affect how quickly your starter rises and ferments.
- whole wheat or rye flour → faster fermentation
- all-purpose or bread flour → more moderate fermentation
Whole wheat and rye flours contain more nutrients and microorganisms that help feed your starter, which can cause it to rise and peak more quickly.
If your starter seems sluggish, adding a small amount of whole wheat or rye flour to your feeding can help boost activity. On the other hand, if your starter is fermenting too quickly, switching to all-purpose or bread flour can help slow things down.
Looking to mill your own grain or use whole wheat flour in your dough? Start here with my Guide to Baking with Whole Wheat Flour.
Choosing the Right Feeding Ratio
I’m a big believer in working smarter, not harder. You shouldn’t be waiting around for your starter to peak. Instead, decide when you want to use your starter and work backwards to figure out when to feed it.
Your feeding ratio is what allows you to control that timing.
A good rule of thumb is to feed your starter at a minimum of a 1:1:1 ratio (equal parts starter, flour, and water by weight).
Feeding more starter than flour and water can cause your starter to become overly acidic. Feeding too much water compared to flour can make your starter very liquid and prevent it from rising well.
How to Choose the Right Ratio
You can adjust your feeding ratio to control when your starter will be ready.
- more starter → faster rise
- less starter → slower rise
- more flour and water → longer fermentation time
This gives you flexibility to make your starter work for your schedule instead of the other way around. At around 78ºF:
- 1:1:1 → ready in about 3–4 hours (same-day baking)
- 1:2:2 or 1:5:5 → ready in 5–8 hours
- 1:10:10 → ready in 10–12+ hours (overnight)
All of these assume a warm environment and a healthy, active starter.
What About a Stiff Starter?
Hydration also plays a role in how your starter behaves.
A stiff starter (one that uses less water) will ferment more slowly, while a looser, more liquid starter will ferment more quickly.
This means a stiff starter can help extend the time before your starter peaks, which is useful if you want a longer fermentation window. A more liquid starter will peak faster and is often easier for beginners to work with.
Most of my recipes use a 100% hydration starter (fed equal weights of flour and water), but I do like using a slightly stiffer starter in recipes like sourdough brioche and sourdough cinnamon rolls.
Sourdough Starter Ratio Chart
The chart below shows common feeding ratios and how they affect timing. These examples assume a temperature around 78ºF and a healthy, active starter fed with bread flour or all-purpose flour.
Use this as a general guide to plan when your starter will be ready.
| Ratio | Example (grams) assuming 78ºF | Ready to Use | Over-ripe (needs to be fed) |
| 1:1:1 | 10 g starter + 10 g flour + 10 g water | 3-4 hours | 7-8 hours |
| 1:2:2 | 10 g starter + 20 g flour + 20 g water | 5 hours | ~ 10 hours |
| 1:5:5 | 10 g starter + 50 g flour + 50 g water | 6-7 hours | 12-14 hours |
| 1:10:10 | 10 g starter + 100 g flour + 100 g water | 10-12 hours | ~ 24 hours |
Timing will vary based on temperature, flour type, and how active your starter is. Using a kitchen scale gives you the most accurate and consistent results. Watch a video example of this process here.
Maintaining a Healthy Sourdough Starter Using Ratios
The more consistently you feed and refresh your sourdough starter, the more active and reliable it becomes. Changing the ratios you use can also help strengthen your starter and make it more resilient.
One of the biggest benefits of understanding feeding ratios is being able to plan your bakes. Instead of guessing when your starter will be ready, you can control the timing by adjusting your ratio and temperature.
Once you get the hang of it, you’ll know exactly when your starter will be peaked and ready to use. That kind of consistency makes sourdough baking so much easier.
Ratios in Your Dough
Once you understand feeding ratios, you can apply the same concept directly to your dough.
Have you ever wondered why some sourdough recipes use 50 grams of starter while others use 100 grams? Or why some doughs can sit overnight while others are ready the same day?
It all comes down to ratios.
The same principles you use to feed your starter apply to your dough. The amount of starter you add affects how quickly your dough ferments and rises.
- more starter → faster rise
- less starter → slower rise
This means you can adjust the amount of starter in your dough to fit your schedule.
If you want to let your dough rise overnight, use less starter and keep an eye on your temperature. A smaller amount of starter combined with a cooler environment will help slow fermentation and prevent over-proofing.
Amy’s Real Life Ratio Tip
You don’t have to be exact every time. I don’t always measure my starter perfectly, but I do make sure I’m feeding it more flour and water than starter. That keeps it healthy and predictable without overthinking it!
Frequently Asked Ratio Questions
Yes. Changing ratios can help strengthen your starter and give you more control over timing. Many bakers adjust ratios regularly depending on their baking schedule.
A 1:1:1 ratio is a great place to start. It’s simple, predictable, and works well for same-day baking. Once you get in the habit of feeding a starter, switch up your ratios to fit your schedule.
No. Ratios are a guide, not a strict rule. Small variations won’t ruin your starter. Once you understand how ratios affect timing, you can adjust them to fit your schedule.
Yes. You can use the same feeding ratios to build a levain as you do for your starter.
If a recipe calls for 120 grams of levain, you can build it using different ratios depending on your timing:
1:1:1 → 40g starter + 40g flour + 40g water
1:10:10 → 6g starter + 60g flour + 60g water
Both will work. The difference is how long it takes to peak. Smaller amounts of starter with more flour and water will take longer, while larger amounts of starter will be ready more quickly.
It’s normal to lose a small amount of weight during fermentation. Some moisture evaporates and gases are released as your starter becomes active.
I usually mix a little extra levain to account for this. If you don’t have quite enough, that’s okay. Just proceed with your recipe and allow a little extra time for fermentation.
What to Do Next
Now that you understand sourdough starter ratios, you can start using them to plan your baking instead of guessing when your starter will be ready.
If you’re new to sourdough, start with my step-by-step sourdough beginner guide or try one of my popular sourdough recipes below.
If you want to go deeper and focus on baking classic artisan-style sourdough bread, check out my artisan bread guide for more advanced techniques.
And if you want everything laid out step by step, I’ve put it all together in my Beginner’s Guide to Sourdough Cookbook and my online sourdough course.
