Enter the weight of the flour (and any other dry ingredients), water (and any other wet ingredients) and starter in the same unit, as they are all the same this calculator will work.There are example usage to show you how to use the form on the menu on the left.There are lots of sample recipes from various sources which I have either develpoed or are from the internet and there is a link back to the,Entering data in the fields will update the Totals as you goThe calculator will work with any hydration starterChanging the unit will convert the formula according to the Conversion Numbers Here You can bookmark the URL to this page with the formula in so you can save multiple formulas without the need to retype the informationYou can change the titles of the Flour / Water by clicking them, this will also be saved with the bookmarkThe Yeasted to Sourdough conversion is an approximation, obviously the rising time will be much longer. You may need to adjust to add more or less starter. Also the flavour will change so if the bread does not taste how you want it to then I would suggest either baking it with yeast or 12-24 hours before you want to bake take 25g of your active starter and add equal amounts of flour and water to bring up to the amount of starter you need. This should reduce the "sour" tasteExtra ingredients can be added that do not affect the hydrationCups .... they hydration % just doesn't work out! The figures I have for converting can't quite be right but searching the interweb they seem to be accurate?!?Different flours can absorb different amounts of water, I created a survey to try and log what hydration different brands of flour can be used at, you can see the results here . You can also complete the survey here if you would like to add flours, it is an open survey.