Converting Yeast Recipes to Sourdough: A Beginner's Cheat Sheet

Converting a commercial-yeast recipe to sourdough isn't complicated. It's two adjustments: replacing the yeast with starter and rebalancing the flour and water. This is the cheat sheet I wish I'd had when I started.

The conversion formula

For every 1 teaspoon (about 3g) of instant or active dry yeast in the original recipe, replace with:

• 100g active sourdough starter (at 100% hydration)
• Subtract 50g flour from the original
• Subtract 50g water from the original

The math: starter is half flour and half water by weight, so you're keeping the original recipe in balance.

A worked example

Original recipe:

• 500g bread flour
• 350g water
• 7g instant yeast (about 2 tsp)
• 10g salt

Sourdough version:

• 500g − 100g = 400g flour
• 350g − 100g = 250g water
• 200g active starter
• 10g salt (unchanged)

Same dough quantity, just leavened differently.

Time adjustments

Sourdough is slower. A yeast recipe that says "1 hour rise" needs 4–6 hours of bulk fermentation as sourdough. Use visual cues, not timers:

• Bulk: dough rises 50–70%
• Final proof: passes the poke test (slow rebound)

If the original recipe has a long cold proof, you can keep that — sourdough loves cold retards.

What works well to convert

• Pizza dough — sourdough version is more flavorful
• Sandwich bread — slightly denser but better keeping
• Focaccia — outstanding as sourdough
• Dinner rolls — soft and complex
• Cinnamon rolls — sourdough discard versions are popular for a reason
• Pretzels and bagels — work great
• Hot dog and burger buns — improved flavor

What converts poorly

• Recipes that depend on a fast rise for texture (some quick breads, certain enriched doughs without a long retard)
• Anything with chemical leavening (baking soda or powder) — those aren't yeast, don't convert
• Pancake or waffle recipes — better to use a discard recipe formula instead

Adjusting for enriched doughs

Brioche, challah, and other enriched doughs need a stronger starter. Use:

• 25–30% starter (instead of 20%)
• Build a stiff levain the night before for extra strength
• Add a longer cold retard to develop flavor without over-fermenting

Eggs, butter, and sugar slow yeast activity, so sourdough enriched doughs need more leaven and more time.

Salt timing

Yeast recipes often add salt at the start. Sourdough recipes sometimes hold salt for autolyse, but for converted recipes, you can mix it in from the beginning unless your original recipe is very high hydration.

Hydration check

After converting, the dough hydration may shift slightly. The starter you add is 100% hydration — if your original recipe was 70%, the new dough is still around 70%. If you used a stiff starter (50% hydration), recalculate the water.

Don't be intimidated

The math looks more complicated than it is. Once you've done two or three conversions, it becomes automatic. Most yeasted recipes you love can be reborn as sourdough with a stronger flavor and longer shelf life.