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
Two 18 g cups daily need 504 g over 14 days. A 250 g stock lasts about 6.94 days; buy at least 254 g for that plan.
Assumptions and limits
Excludes grinder purge, spills, visitors and changing recipes. A stock-duration estimate says nothing about bean freshness; buy quantities you can store appropriately.
Questions
What does this result establish?
Daily coffee = cups × dose. Period use = daily coffee × days. Required purchase is period use minus stock, floored at zero. It provides the stated arithmetic or random ordering; it is not a taste or equipment certification.
What measurements should I use?
Cups per day; Coffee per cup (g); Planning period (days); Current bean stock (g). 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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