About Sourdough Maths
Sourdough Maths is a small, free tool that helps home bakers turn the recipe they have in their head into exact gram weights. No fluff, no life story before the recipe, no thirty-paragraph preamble standing between you and the numbers. You tell it how many loaves, what size and how wet you want the dough, and it works out the flour, water, starter and salt to the gram using baker's percentages. Around the calculator sits a small library of plain-English articles and guides to fill in the gaps, written for people who just want to bake good bread.
Why this exists
Every existing online calculator we tried was one of three things: choked with ads, quietly wrong about the maths, or buried under a 2,000-word blog post when all we wanted was four numbers. Sourdough is intimidating enough for a beginner without a tool that makes you scroll past someone's holiday photos to find a hydration figure. We wanted the opposite: get the numbers fast, then learn the why at your own pace if you feel like it.
Who makes it
The site is built and maintained by Mark Stent, a software engineer and a stubborn home baker. He writes the calculator, the guides and the maths-heavy explainers, and he is the one to email when a number looks wrong.
The recipes and bake-along articles are written and tested by Ashleigh Stent, who does the actual baking. Every recipe on the site has been mixed, proofed and baked in a normal home kitchen, not just typed out from theory. If a timing or a hydration is on the page, it is because a real loaf came out of the oven at the end of it.
How we write and check things
- The maths are the standard baker's percentage system used by professional bakers. The formulas are open and explained in full on the baker's percentage guide, so you can check our working.
- Every recipe page is generated from the same underlying calculator, so the numbers are consistent across the entire site. There is one formula, not dozens of hand-typed recipes that can drift apart.
- The flour-type hydration adjustments are based on widely accepted ratios from home and professional baking sources, and we say plainly when something is a rule of thumb rather than a law.
- Recipes and techniques are tested by baking them, not just researched. Where a method has trade-offs, we describe them instead of pretending there is one right answer.
- If you find something wrong, tell us. We correct mistakes quickly and we would rather be right than look right.
What you will find here
Alongside the calculator there is a timeline planner that turns a target bake time into exact clock times for each step, a growing set of recipes and guides, a plain-English glossary of sourdough terms, and a troubleshooting page that goes symptom, cause, fix for the problems every baker eventually hits.
How the site stays free
The free tier is supported by display ads. A paid subscription removes ads and unlocks recipe saving plus a bake log. See pricing for the details. Either way, the calculator and every recipe page stay free for everyone, forever. The ads pay for the hosting, not for a yacht.
Contact
Questions, corrections, or feature requests are all welcome on the contact page. Corrections especially: if a recipe did not work for you, we want to know why.