Batch size before guesswork

Cold brew ratio calculator

Size coffee and water to the vessel, then treat retained water and serving dilution as explicit estimates.

Vessel-aware sizing

Plan the batch

Nothing here promises a final beverage yield; grounds retain water differently.

Changes the suggested starting ratio, not a guarantee.

ml

CupTune treats 1 ml water as approximately 1 g for sizing.

1 : x

Try 1:15 ready to drink or 1:5 concentrate.

%

Space for grounds, stirring and safe handling.

Serving concentrate

Measure concentrate and its current TDS, then choose a lower target. CupTune uses mass balance: final mass = concentrate × current TDS ÷ target TDS.

Open the cold brew recipes and handling guide.

SCA cold-brew research found that extraction behaviour varied with temperature, coffee origin and roast, so the calculator does not promise one steep result.

Food handling

FDA storage guidance says to refrigerate prepared food promptly, within two hours, and keep a refrigerator at or below 40 °F (4 °C). CupTune does not assess microbial safety or shelf life.

Questions before the next brew

Does CupTune upload my brew journal?

No. Recipes, timer state, bean details, measurements and notes stay in this browser unless you explicitly export a file.

Does CupTune decide whether coffee tastes correct?

No. It keeps measurements comparable and suggests one controlled change; taste remains your preference.

Can I use the tools offline?

After one successful load, the application shell and authored routes are cached. Advertising, analytics and email links can be unavailable without blocking the tools.

Why does extraction yield require TDS?

Extraction yield needs a measured dissolved-solids value. CupTune will not invent one from roast, colour, method or taste.