Dough ratio
Starter : water : flour, by weight. 100 g starter, 200 g water, 300 g flour gives a 600 g beginner boule at about 71% overall hydration.
Sourdough · Calculator
Sourdough Ratio Calculator
Scale the classic 1:2:3 dough ratio — 1 starter, 2 water, 3 flour — or any starter feeding ratio to exact grams, with overall hydration worked out for you.
Live calculator · updates as you type
Your ratio
What are you scaling?g
Dough ratio (starter : water : flour)Mix this dough
Flour 300g
Water 200g
Starter100 g
Overall hydration71%
Total dough 600 g
Starter Flour Water
What to do next
What to do next
For 600 g of dough.
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Common dough ratios
| Ratio (S:W:F) | Best for | Notes |
|---|---|---|
| 1:2:3 | The classic beginner boule | Balanced, forgiving, about 71% overall hydration |
| 1:3:5 | Firmer sandwich-style dough | Lower hydration, easier to shape |
| 1:4:6 | Larger, leaner batch | Less starter share, slower ferment |
| 1:2.5:4 | Open-crumb artisan loaf | About 67% overall hydration with a 100% starter |
The 1:2:3 ratio is 1 part starter, 2 parts water, 3 parts flour by weight — a classic beginner formula at about 71% overall hydration once the starter is counted.
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Sourdough Starter Manager
Log each feed, watch your starter rise in a 3D jar and record when it peaks. After two feeds it learns your own starter’s timing, so you know when it will be ready.
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Sourdough ratio guide
The two ratios sourdough bakers mean
"Ratio" gets used two ways in sourdough. This calculator handles both — the dough mixing ratio you build a loaf from, and the feeding ratio you keep your starter alive with.
Counting the starter, that is about 71% hydration. Change the ratio below.
Use these reference values to interpret your results
- 1 : 2 : 3
- 1 : 5 : 5
Feeding ratio
Starter : flour : water, by weight. Higher ratios give more food per gram of starter, so the peak comes later and the flavour is milder.
Use the results in your next batch
Every sourdough ratio is by weight in grams — a scale is essential, because flour, water, and starter all weigh differently. To turn a target hydration into weights instead, use the hydration calculator; to feed an existing jar to a set amount, use the feeding calculator.
FAQ
Sourdough ratio questions
The 1:2:3 dough ratio, starter feeding ratios, and how to use them by weight.
What is the 1:2:3 sourdough ratio?
The 1:2:3 ratio is a simple sourdough dough formula: 1 part sourdough starter, 2 parts water, and 3 parts flour, all by weight. For example, 100 g starter, 200 g water, and 300 g flour makes a 600 g dough. Counting the starter as flour and water, that lands at about 71% overall hydration — an approachable beginner boule.
How do I use the sourdough ratio calculator?
Pick a mode. In dough mode, enter the amount of starter you have and choose or type a ratio (starter : water : flour); the calculator returns the water and flour to add, the total dough weight, and the overall hydration. In feeding mode, enter the starter you are keeping and a feeding ratio (starter : flour : water) such as 1:1:1 or 1:5:5 to get the flour and water to feed.
What is a good starter ratio for sourdough?
For maintenance, 1:1:1 (equal starter, flour, water) peaks fastest, about 4–6 hours at 75°F / 24°C by my estimate, and tastes the tangiest. 1:5:5 gives the starter more food per gram, peaks later (about 10–14 hours) and tastes milder, which suits overnight schedules. Those times are planning estimates, so learn your own jar. For dough, the 1:2:3 mixing ratio is the standard starting point.
Is the sourdough ratio by weight or volume?
Always by weight, in grams. Sourdough ratios only work reliably with a scale, because flour and water have very different densities and starter is heavier than either. Volume measures (cups and spoons) drift too much for a ratio to hold, so weigh every part.
Does the 1:2:3 ratio include the flour and water in the starter?
The 1:2:3 mixing ratio counts the starter as one whole part, but a 100% hydration starter is itself half flour and half water. This calculator factors that in when it reports overall hydration, so the percentage reflects the true flour and water totals, not just the added amounts.
From our shop
Printed book · Delivered to you
The Sourdough Log
A spiral-bound book delivered to your door, ready to write in. 52 bake records in a spiral-bound journal that lies flat.
Digital download · Print at home
The Sourdough Log
Download the files and print your own copy. No book is shipped. 52 guided bake spreads to download and print at home.
Digital download · Print at home
The Sourdough Formula Book
Download the files and print your own copy. No book is shipped. Baker's percentages, worked out for you.
Download the free Sourdough Baking Playbook
One printable PDF covering core sourdough methods — hydration, starter, feeding, levain, bulk fermentation, and discard.
Continue with the next calculator
Calculators and guides for your next step.
- Feeding calculator Calculator · Feed an existing jar to a target amount at any ratio.
- Hydration calculator Calculator · Set flour and water from a target hydration.
- Discard calculator Calculator · Turn starter discard into recipe-ready substitutions.
- All sourdough calculators Category · Every sourdough tool and guide in one place.
