Sourdough Starter Calculator
Calculate exactly how much flour and water to add to your existing starter. Adjust the target amount and hydration while keeping your feeding accurate and waste low.
Add its total weight and current hydration percentage.
Set the amount and hydration needed for your bake.
Use the calculated flour and water additions.
Hydration is converted from a percentage to a decimal. The calculator separates both the current and target starter into flour and water, then finds the difference.
Starter hydration compares water weight with flour weight. A 100% hydration starter contains equal weights of flour and water. A 75% starter is stiffer, while a 125% starter is wetter and more fluid.
A feeding can only add flour and water. When the target requires less flour or water than your current starter already contains, discard some starter first or choose a larger target amount.
What is a 1:1:1 sourdough feeding?
It means equal weights of starter, flour, and water. For example, 50 g starter, 50 g flour, and 50 g water.
Can I calculate a stiff starter?
Yes. Enter a target hydration below 100%, such as 60% or 75%, to calculate a firmer starter.
Why does the calculator show an impossible build?
Your existing starter may already contain more flour or water than the chosen target allows. Reduce the seed starter or increase the target amount.
Results are estimates generated locally in your browser using standard formulas and general assumptions. They are for informational purposes only and may not reflect your specific circumstances. VisionVix accepts no liability for decisions based on this tool's output.
This calculator provides weight-based estimates for starter feeding and hydration. Flour absorption, room temperature, starter activity, and fermentation time can affect actual baking results.
