Installed. Now pin it to the toolbar
Keep Sourdough Calculator one click away:
- Click the puzzle-piece icon (Extensions) to the right of the address bar.
- Find Sourdough Calculator in the list and click the pin next to it.
- Its icon now stays in the toolbar. Click it whenever you need the extension.
Sourdough calculator: every gram of your dough from baker's percentages
Set the hydration, the starter and the salt, and the popup shows the grams of water, levain and salt, the total dough weight and the true hydration with the starter counted in. Then start the bulk timer.
A free Chrome extension that works out the ingredient weights of a bread, pizza or focaccia dough from baker's percentages and times its bulk fermentation and folds. The extension is on its way to the Chrome Web Store. The install button appears here as soon as it is published.
- Baker's %
- Loaf · Pizza · Focaccia
- Bulk timer · QR

How to calculate a sourdough with baker's percentages
- Click the toolbar button to open the popup.
- Pick a preset: sourdough loaf, pizza or focaccia.
- Enter the flour weight, or the finished dough you want, such as 6 pizzas of 250 g.
- Read the grams, copy or print the formula, and start the bulk timer when you mix.
What you get
Baker's percentages
Every ingredient is a share of the flour, so one formula scales to any batch. Each line shows the grams next to the percentage.
True hydration
A starter at 100% is half flour and half water. The calculator adds the levain's flour and water to the totals, so the hydration you see is the one your hands will feel.
Pizza and focaccia too
Presets for a sourdough loaf, Neapolitan and New York pizza and focaccia. Size by dough (6 pizzas of 250 g, one loaf of 900 g) and use instant yeast instead of a starter if you like.
Bulk-ferment timer with folds
The bulk time is estimated from your dough temperature and you can edit it. Stretch-and-fold reminders come at the interval you choose; the minutes left show on the toolbar button.
Reads a recipe page
Open the popup on a bread or pizza recipe page and it shows the recipe's flour, water, starter and salt as baker's percentages, ready to scale.
My doughs and your phone
Save formulas in My doughs with export and import. Scan a QR code and the formula and the running timer open on your phone.
Screenshots




Your doughs stay in your browser
Everything runs on your computer: no account, no analytics and no network requests. Settings, saved doughs and the timer stay in Chrome's storage on this device.
Open on your phone puts the formula and the timer inside the link itself, after the # sign, which browsers never send to a server.
Questions and answers
What is baker's percentage?
Each ingredient is a percent of the total flour weight, which counts as 100%. At 75% hydration, 1000 g of flour takes 750 g of water.
Does it count the water in my starter?
Yes. The overall hydration includes the levain's flour and water, at the starter hydration you set (100% by default).
Does it work for pizza?
Yes. Choose a pizza preset, enter the number of dough balls and their weight, and use instant yeast instead of a starter if you like.
How long should bulk fermentation take?
It depends on how warm the dough is. The timer suggests a time for sourdough from your dough temperature, which you can change. Watch the dough, not only the clock.
Which languages does it speak?
The interface is in 15 languages, including English, German, French, Spanish, Japanese and Korean.
Is it free?
Yes. Every feature is free and works without an account.
Help and support
Sourdough Calculator
A free Chrome extension that works out the ingredient weights of a bread, pizza or focaccia dough from baker's percentages and times its bulk fermentation and folds.
Fermentation times are estimates: every flour, starter and kitchen is a little different. The extension is not affiliated with any recipe website.