Skip to main content
DigiCalcs

How to Calculate Sourdough

What is Sourdough?

Sourdough baking uses baker's percentages where all ingredient quantities are expressed as a percentage of total flour weight. This allows recipes to scale easily to any batch size. The starter (levain) contributes its own flour and water to the dough.

Formula

Hydration % = Water weight ÷ Flour weight × 100

Step-by-Step Guide

  1. 1Set total flour as 100% — all other ingredients are percentages of this
  2. 2Hydration % = Water weight ÷ Flour weight × 100
  3. 3Starter % = Starter weight ÷ Flour weight × 100
  4. 4A 100% hydration starter contains equal weights of flour and water
  5. 5Adjust the main water to account for water already in the starter

Worked Examples

Input
500g flour, 75% hydration, 20% starter
Result
375g water total, 100g starter
Main water = 375 − 50 = 325g (50g from starter)
Input
1000g flour, 80% hydration, 15% starter
Result
800g water, 150g starter
Starter provides 75g flour + 75g water

Frequently Asked Questions

What is Sourdough?

Sourdough baking uses baker\. Use this calculator for accurate, instant results.

How accurate is the Sourdough calculator?

The calculator uses the standard published formula for sourdough. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Sourdough calculator use?

This calculator works with inches, percentages, watts. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Sourdough calculator use?

The core formula is: Hydration % = Water weight ÷ Flour weight × 100. Each step in the calculation is shown so you can verify the result manually.

Ready to calculate? Try the free Sourdough Calculator

Try it yourself →

Settings

PrivacyTermsAbout© 2026 DigiCalcs