A Guide to Sourdough Feed Ratios (And How to Actually Use Them)

Feed ratios confuse a lot of new sourdough bakers, but the concept is genuinely simple once it clicks. A feed ratio tells you the proportion of starter to water to flour in your feed, and it is one of the most useful tools you have for controlling how quickly your starter or levain reaches peak

8/27/20263 min read

Confused by sourdough feed ratios like 1:1:1 or 1:5:5? This guide explains exactly what they mean, how to choose one, and how to use ratios to control your starter’s timing.

How to Read a Feed Ratio

A ratio like 1:2:2 means 1 part existing starter, 2 parts water, 2 parts flour, by weight. The starter number is always shown as 1, because it is the constant you are comparing everything else against.

The Golden Rule

Lower starter percentage (a higher ratio, like 1:10:20) means a slower rise and a longer time to peak (maximum yeast population growth) - this is because you've provided a small amount of your wild yeast with a large amount of food. Higher starter percentage (a lower ratio, like 1:1:1) means a faster rise and a shorter time to peak since your yeast don't have a lot of food to much on. More total flour and water means a longer fermentation overall, simply because you have given the yeast more food to work through.

Why Ratio Choice Matters Beyond Just Timing

A higher proportion of starter within your feed can actually make your starter more acidic more quickly, which in turn can inhibit rise. This is part of why very high starter ratios (like 1:1:1) are not always ideal for ongoing maintenance feeds, even though they work well for quickly establishing a brand new starter or for a levain you need ready in a hurry.

I'm a fan of a stiffer starter/levain (lower hydration, around 50 to 60 percent). These ferment more slowly than a regular hydration one, which is useful if you want your fridge starter to last longer between feeds, or if you want your levain to take longer to reach peak so it lines up with your schedule. These also result in a less sour taste if that is something you want to achieve.

Common Feed Ratios and What They Are Good For

1:1:1 – Fast, useful for establishing a brand new starter or for a same-day levain, but too much maintenance for regular ongoing feeds unless you are feeding multiple times a day.

1:2:2 or 1:2:3 (stiff) – A solid everyday choice for both starter maintenance and levain building, with a moderate time to peak. An 8am 1:2:3 levain is my favourite option when I want to prep, mix & proof my dough all in one day ready to bake first thing the next morning.

1:3:3 of 1:3:5 (stiff) – A good middle ground if you want your levain ready in around half a day rather than a few hours.

1:5:5 to 1:10:20 (stiff) – Ideal for a fridge-maintained starter you only want to feed roughly weekly. The high food ratio combined with fridge temperatures slows everything down considerably.

1:20:20 and beyond – Very slow, generally used for longer storage gaps or very deliberate slow fermentation schedules. You may end up only using a smear of your existing starter to make the next one.

How to Choose Your Ratio

Start by thinking about your schedule rather than picking a ratio at random. If you want your levain ready in the evening after making it in the morning, choose a ratio and temperature combination that gets you there, then keep it consistent so you learn exactly how your starter behaves. If you are not baking often, use a higher ratio and keep your starter in the fridge so you are not feeding daily and generating unnecessary discard (unless you want regular discard to use in recipes).

A Practical Tip

Whisk your starter fully into your water before adding the flour. It is far easier to combine starter and water thoroughly first, since flour can make full incorporation trickier, and thorough mixing before adding flour helps to aerate the starter, giving the yeast more oxygen to help reach peak activity.