Food

Sourdough Ratio Calculator (Baker's Percentages)

Turn baker's percentages into exact gram weights for flour, water, starter and salt.

Enter your values

Enter the total flour in g.

Enter the hydration in %.

Enter the starter / levain in %.

Enter the salt in %.

Enter the starter hydration in %.

Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.

Results
Flour to add
450 g
Water to add
325 g
Starter
100 g
Salt
10 g
Total dough weight
885 g
Overall hydration
75 %

Starter flour and water are counted in the totals.

IngredientGramsBaker's %
Flour (total)500100%
Water (total)37575%
Starter10020%
Salt102%

Quick answer

Baker's percentages express every ingredient as a share of flour weight. For 500 g flour at 75% hydration, 20% starter and 2% salt you need 375 g water, 100 g starter and 10 g salt.

ingredient grams = flour grams × baker's percentage

At a glance

What it doesTurn baker's percentages into exact gram weights for flour, water, starter and salt.
CategoryFood
Inputs neededTotal flour, Hydration, Starter / levain, Salt, Starter hydration
Main outputFlour to add
Formulaingredient grams = flour grams × baker's percentage
CostFree — no sign-up, no download

How to use the Sourdough Ratio Calculator

  1. 1Enter your target total flour weight.
  2. 2Set hydration, starter and salt percentages.
  3. 3Weigh out the adjusted flour and water amounts.

Inputs explained

Total flour(g)
Enter the total flour in g.
Hydration(%)
Enter the hydration in %.
Starter / levain(%)
Enter the starter / levain in %.
Salt(%)
Enter the salt in %.
Starter hydration(%)
Enter the starter hydration in %.

Worked example

Using the values the calculator loads with:

Inputs

  • Total flour500 g
  • Hydration75 %
  • Starter / levain20 %
  • Salt2 %
  • Starter hydration100 %

Results

  • Flour to add450 g
  • Water to add325 g
  • Starter100 g
  • Salt10 g
  • Total dough weight885 g
  • Overall hydration75 %

Frequently asked questions

What hydration should a beginner use?

65–70% is far easier to shape. Move to 75–80% once you are comfortable with stretch and folds.

Why subtract starter flour and water?

A 100% hydration starter is half flour, half water. Counting it keeps your true hydration accurate instead of accidentally wetter than intended.

What do I need to enter into the Sourdough Ratio Calculator?

Just 5 values: total flour, hydration, starter / levain, salt, starter hydration. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.

How does the Sourdough Ratio Calculator work out the answer?

Baker's percentages express every ingredient as a share of flour weight. For 500 g flour at 75% hydration, 20% starter and 2% salt you need 375 g water, 100 g starter and 10 g salt. It applies the formula ingredient grams = flour grams × baker's percentage and shows the working so you can check each step by hand.

Is the Sourdough Ratio Calculator free, and do I need an account?

It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.

Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.