Have you ever found a sourdough recipe you loved, then needed to change the number of loaves, adjust the hydration or replace part of the flour? Suddenly, what looked like a simple bake becomes a page full of calculations.

When you bake regularly — especially when you are moving from a home kitchen towards a microbakery — those numbers matter. A small change in hydration, starter quantity or flour blend can change both the dough you handle and the schedule you work around.

I wanted a tool that would make that side of bread making easier, without taking the baker out of the process. That is what Sourdough Precision is for: a free online sourdough recipe calculator developed around practical baking decisions and connected to my baking work at Healthy Nasti Kitchen.

The calculator now has a home on SA Bakery Supplies. You can find it on our new Recipe Calculator page, alongside the baking education and microbakery resources we are building.

Why I believe every serious baker should understand their numbers

You can follow a recipe once and make a beautiful loaf. But if you want to make that bread consistently — or produce more than a few loaves — you need to understand the relationship between its ingredients.

Baker’s percentages use total flour as the reference point. If your formula calls for 75% hydration, that means 75 grams of water for every 100 grams of total flour, allowing for how the formula accounts for the flour and water already in your starter. The percentages make it possible to compare formulas and scale them intelligently.

The real value is freedom: freedom to plan ten loaves instead of two, try 30% rye in a white-wheat dough, or experiment with a different dough weight without starting from zero each time.

1. Recipe Calculator: adjust your recipe to the bake you actually want

The Recipes section is your starting point. Choose a bread style — from sourdough loaves and baguettes to focaccia, ciabatta and other doughs — then set how many pieces you want to make and their individual dough weight.

Adjust the hydration and, in the advanced settings, refine quantities such as starter percentage, starter hydration, salt and optional dried yeast. The app calculates gram weights for the ingredients and the overall dough quantity.

That means you can explore how a recipe changes before weighing your flour. It is a calculator, not a replacement for reading your dough: flour absorption, temperature, fermentation and handling still matter.

2. Flour Blend Builder: make the recipe yours

This is one of the features I particularly like for sourdough baking. Not everyone wants to use 100% white flour. You might want to make a loaf with 70% white wheat flour and 30% wholemeal, or introduce rye, seeds or another grain into your mix.

In the Blend section, you can build a custom flour combination, adjust the ingredients and calculate the quantities for your intended batch. It encourages experimentation while keeping the numbers organised.

For someone developing their own signature sourdough loaf — whether at home or for a future microbakery menu — that is extremely useful.

3. Custom Recipes: work beyond a fixed formula

The Custom section is for bakers who want to create their own formulas rather than rely only on preset bread styles. Set up the recipe that fits your approach, adjust its proportions and use the calculator to translate your formula into a workable ingredient list.

This is where the app becomes more than a quick hydration calculator. It becomes somewhere to develop recipes as your knowledge and style evolve.

4. My Recipes: save, edit and return to your best formulas

When you find a formula that works, you do not want to lose it. The Saved Recipes section lets registered users keep their formulas, reopen them for editing, duplicate a version and remove one they no longer need.

This can be particularly useful for comparing iterations. Maybe your first loaf was too tight at 68% hydration, but your next test at 74% was a big improvement. Rather than trying to remember every adjustment, you can build on the recipe you already saved.

Recipes are connected to your individual app account. You will need to sign up or log in to use the calculator, and your Baking Journal email subscription is separate from your app login.

5. Teach Me: connect the numbers with actual baking

A calculation makes more sense when you can see the process behind it. The app also includes a Teach Me section connected to Healthy Nasti Kitchen, where you can explore relevant bread-making videos.

I have always believed that understanding what happens in your hands — mixing, folding, shaping and fermentation — is every bit as important as understanding a formula on paper. The app and the YouTube channel are designed to support each other.

6. Professional baking guidance and sourdough starter care

The app also offers a Pro Guide and Starter Care section. The professional guide uses clear visual examples of dough rise stages and the poke test. The starter-care section explains a simple four-step routine — discard, feed, mix and wait — as a starting point for building a reliable starter routine.

A feeding schedule is a useful guide, not a guarantee: how quickly a starter rises depends on temperature, flour choice and its condition. Learn to recognise its activity and the point at which it is ready to use. If you would like to explore that subject further, read our Journal article, How Your Sourdough Starter Affects the Finished Loaf.

Who is Sourdough Precision for?

I see this tool being useful to three types of bakers: the home baker who wants to adjust recipes with confidence; the aspiring microbakery owner who needs to calculate bigger batches consistently; and the experienced baker who wants a practical place to build, save and revisit formulas.

The app works as a mobile-friendly web application, offers English and Italian language options and can be added to a compatible device’s home screen. It is built to fit into the way bakers actually work — often with flour-covered hands and very little spare time.

How to get started

Visit the SA Bakery Supplies Recipe Calculator page, open Sourdough Precision, and create an account or sign in. Choose an existing bread recipe, enter your batch quantity and hydration, then explore the calculations. When you like your formula, save it so you can come back to it on your next baking day.

A final word from one baker to another

The more bread I bake, the more I believe that good baking comes from combining experience with understanding. You need to feel the dough, observe fermentation, and know how your ingredients behave. But you also need a reliable way to work out the numbers.

Sourdough Precision is my way of bringing those two sides of baking a little closer together. I hope it helps you spend less time wondering whether your calculations are right and more time enjoying the bread you are creating.

Explore the calculator through SA Bakery Supplies, then continue learning with The Baking Journal and Healthy Nasti Kitchen.

Keep learning: get the Baking Journal by email

If you would like practical sourdough tutorials, recipe experiments and updates from SA Bakery Supplies and Healthy Nasti Kitchen, you can join the free Baking Journal. It is optional and separate from creating an app account. You will receive a subscription confirmation email, and you can unsubscribe anytime.

Frequently asked questions

Is the sourdough recipe calculator free?

Yes. Sourdough Precision is presented as a free recipe calculator. You need an app account to use it and to access saved recipes.

Can I change the hydration and number of loaves?

Yes. You can change the number of pieces, dough weight per piece and hydration, with additional formula adjustments available in the calculator.

Can I save my own sourdough recipes?

Yes. Registered users can save recipes, reopen them for editing and duplicate versions of formulas they want to refine.

Can I use the calculator for a microbakery?

Yes. Batch scaling and custom flour blends can be useful in microbakery planning, although production schedules, fermentation conditions and food-safety systems still require professional judgement.