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
300 g at 90°C from 100°C and 20°C water needs 262.5 g hot and 37.5 g cold water.
Assumptions and limits
Ideal heat balance for liquid water with equal heat capacity; ignores vessel heat, evaporation and environmental cooling. Measure the final temperature. Handle hot water carefully.
Questions
What does this result establish?
Hot mass = total × (target − cold) / (hot − cold). Cold mass is the remainder. It provides the stated arithmetic or random ordering; it is not a taste or equipment certification.
What measurements should I use?
Hot water temperature (°C); Cold water temperature (°C); Target mixed temperature (°C); Total mixed water (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.
Related tools
Recipe Batch Scaling
Multiply every ingredient by new water / original water.
Open tool →Iced Pour-Over Water and Ice
Total water = dose × ratio. Ice = total water × ice share. Hot water is the remainder.
Open tool →Staged Pour Planner
Subtract bloom from total water and divide the remaining water into equal additions. Results distinguish added and cumulative weights.
Open tool →