Starter Discount Calculator

The calculator below applies starter discount automatically. Set levain % and levain hydration — the "flour to add" and "water to add" outputs are what you actually weigh out on your counter.

Flour to add
450 g
Water to add
325 g
Salt
10 g
Levain @ 100%
100 g
Total dough
885 g
Effective hydration
75%
How the math works

Total water = flour × hydration %. Your levain contributes 50 g flour + 50 g water — both count toward the totals. You add only the remainder as fresh flour and water.

Salt % is computed on total flour weight, not final-dough flour.

Open 75% hydration guide →

The math, explained

If you're using a 100% hydration levain at 20% of recipe flour weight, the levain contributes 10% of recipe flour weight in flour and 10% in water. A stiff (50% hydration) levain at 15% of recipe flour contributes 10% flour and 5% water. The calculator above handles the math for both — you only see the "flour to add" and "water to add" rows, which are the actual weights you measure.

The gear that makes the math work

A short, honest baking kit. The scale matters most — every weight on this page is in grams. The Dutch oven is what turns a good crumb into a great crust.

  • Digital kitchen scale (0.1 g)

    Baker's percentage is by weight, not volume — a 0.1 g scale is what makes the math on this page accurate.

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  • Dutch oven / combo cooker

    Traps steam for the first bake phase — the single biggest factor in oven spring and a blistered, glossy crust.

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  • Banneton proofing basket

    Wicks moisture and holds shape during the final proof, so high-hydration dough doesn't spread flat.

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  • Bread lame

    A sharp lame scores clean ears — the cut that decides whether the loaf opens up or bursts at the side.

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  • Bench scraper

    Steel scraper handles wet, sticky high-hydration dough without tearing the gluten you just built.

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  • High-protein bread flour

    The math assumes ~12–14% protein. Real bread flour absorbs the hydration you calculate — all-purpose won't.

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  • Danish dough whisk

    Mixes shaggy, high-hydration dough in seconds without the gluey mess of a spoon or your hands.

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🎧 Or learn the craft by ear

The numbers here are the what; a good baking book is the why. An Audible trial gets you any title free — Michael Pollan’s Cooked(the “Air” chapter is the best story ever told about why bread rises) is a perfect first listen.

Start a free Audible trial →

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