Does the ratio have to be the same for flour and water?

No. The ratio format is starter : flour : water. You can use different flour and water amounts to control hydration. For example, 1:2:3 means one part starter, two parts flour, three parts water — a 150% hydration starter.

Can I use a 1:10:10 ratio?

Yes, but only for a healthy, active starter. A very weak or sluggish culture won't be able to metabolise that much food and will peak poorly. Build up to high ratios gradually.

What happens if I use more starter than the ratio suggests?

More old starter means more existing yeast and bacteria — the culture peaks faster. It also means more accumulated acid from the old starter, which can produce a more sour result and a faster collapse after peak.

Why does my 1:5:5 starter taste more mild than my 1:1:1?

Because the large food supply relative to the starter seed dilutes the acid load. The milder result at peak is expected — if you want more tang at 1:5:5, let it go a little past peak before using.

How do I calculate how much to feed?

Use the sourdough feeding calculator — enter the ratio, your target amount, and it gives you exact grams of starter, flour, and water to use.

Sourdough Starter Feeding Ratios Explained — Ferment Calculator

A sourdough starter feeding ratio tells you how much old starter, flour, and water to combine for each feed — three numbers in the format starter : flour : water, always by weight. The ratio you choose directly controls how fast your starter peaks, how acidic it becomes, and how neatly it fits your baking schedule.

What the three numbers mean

Each number is a proportion of the one before it, measured by weight. A 1:1:1 feed with 20g of old starter takes 20g flour and 20g water. The three ratios below cover almost everything a home baker needs.

1:1:1 — equal parts 20g starter + 20g flour + 20g water (60g total). Peaks fast, about 4–6h at 24°C. Best for same-day baking, daily counter maintenance, or reviving a sluggish starter.

1:2:2 — double the food 20g starter + 40g flour + 40g water (100g total). Peaks in 6–10h at 24°C. A good overnight ratio: feed at night, use in the morning.

1:5:5 — slow build 10g starter + 50g flour + 50g water (110g total). Peaks in 10–14h at 24°C. Dilutes the acid for a milder starter and paces long or warm-kitchen builds.

How ratio affects peak timing

At the same temperature, peak timing scales roughly with the amount of food. Doubling it (1:1:1 → 1:2:2) roughly doubles the time to peak; going to 1:5:5 stretches it by about 3–4×. A 1:3:3 feed sits in between at 8–12 hours, and 1:10:10 can take 14–20 hours.

4–6h 1:1:1 at 24°C

6–10h 1:2:2 at 24°C

10–14h 1:5:5 at 24°C

Temperature has a larger effect than ratio — a change of about 4°C can halve or double peak time regardless of the ratio you pick. Use the sourdough feeding calculator to line your feeds up with your baking schedule.

How ratio affects flavour

A lower ratio means less food per unit of starter, so the culture eats through it faster and builds acid more quickly — a tangier, more assertive result. A higher ratio dilutes the acid and produces a milder starter at peak.

Low ratio (1:1:1) faster acid build and more tang; go slightly past peak for a very sour loaf.

Mid ratio (1:2:2 – 1:3:3) balanced flavour with a workable overnight window.

High ratio (1:5:5+) diluted acid and a mild, clean flavour; ideal for showcasing a specific grain.

Hydration and ratio are separate things

The feeding ratio describes the proportions of starter, flour, and water. Hydration — water as a percentage of flour — is a separate property you set by changing the flour-to-water part of the ratio.

1:2:3 → 150% hydration More water than flour makes a loose, liquid-like starter — more active and bubbly.

1:2:2 → 100% hydration Equal flour and water: the standard, easiest to calculate and observe.

1:2:1.6 → 80% hydration Less water makes a stiffer starter — more compact, tends to a more acidic flavour.

Stiff starters (50–70%) lean acidic and hold a compact structure; liquid starters (100–150%) are more active and open. Most home bakers use 100% because it is the simplest to read.

Custom ratios

There is nothing magic about 1:1:1 or 1:5:5 — they are just round numbers that are easy to remember. Any ratio that fits your schedule works. A 1:3:3 gives a comfortable 8–10 hour window; a 1:1:2 makes a looser 200% hydration starter with a faster peak than 1:2:2; a 2:5:5 maintains a larger volume without discarding as much.

The key is consistency. Pick a ratio, stick to it, and learn how your starter behaves at a given temperature. Once you know its timing, you can plan bakes precisely. To turn any ratio into exact flour, water, and discard weights for your jar, use the sourdough starter calculator.

Which ratio should you use?

Match the ratio to how often you bake and how sour you like your bread.

Bake every day or two 1:1:1 on the counter, once daily. Fast, reliable, always ready.

Bake 2–3 times a week 1:2:2 or 1:3:3 on the counter, fed in the evening for a morning bake.

Bake once a week Store in the fridge; feed 1:5:5, let it peak at room temp, use, then return to the cold.

Dial the sourness Want more tang? Use 1:1:1 and go slightly past peak. Want less? Use 1:5:5 and catch it right at peak.

Try the calculator

Sourdough Feeding Calculator

Enter your ratio and target amount for exact grams of starter, flour, and water.

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