Runs on this device. Inputs are not uploaded or saved. Results rounded for display.
How to use it
- Measure the inputs in the units shown. Keep a note of your original recipe.
- Change the relevant input and calculate. Compare the answer with the worked example below.
- Use the output within the stated limits; reset to restore the example inputs.
Worked example
100 ppm as CaCO3 is about 5.603°dH, 5.842 US gpg and 10°fH.
Assumptions and limits
Only converts equivalent reporting units. ppm of calcium ions or an arbitrary TDS reading is not ppm as CaCO3. GH and alkalinity are different measurements even if expressed in the same units.
Questions
What does this result establish?
Convert CaCO3-equivalent concentration using 17.848 ppm per German degree, 17.118 ppm per US grain/gallon, and 10 ppm per French degree. It provides the stated arithmetic or random ordering; it is not a taste or equipment certification.
What measurements should I use?
Hardness (ppm as CaCO3). Keep the units consistent rather than copying a number from a differently labelled recipe.
Why is an input rejected?
Blank, non-finite, negative or out-of-domain measurements cannot produce a valid answer. Each field has a bounded range. Incompatible combinations show an explanation instead of retaining a previous result.
Can I use this without an account?
Yes. Once this page and its modules load, the calculation runs locally without accounts, external APIs or input storage. Reloading restores the defaults.
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