Plan · brew · learn

Tune the cup, not your memory.

CupTune connects a ratio calculator, guided timer, private brew journal and one-variable dial-in guide. No account. Your coffee notes stay in this browser.

Plan this brew

Works offline after the first load. Export before clearing browser data.

Start with the ratio

Quick brew plan

Set dry dose and ratio. CupTune derives water and keeps the arithmetic visible.

g

Measured dry dose.

1 : x

Water mass divided by dry dose.

g

Edit this or let dose × ratio derive it.

One connected loop

From plan to next move

  1. 01

    Plan

    Choose dose, ratio and a recipe you can repeat.

  2. 02

    Brew

    Follow absolute time and cumulative targets.

  3. 03

    Record

    Keep actual measurements and taste locally.

  4. 04

    Tune

    Change one controllable variable next time.

Browser-local continuity

Your last brew can resume here

No active session on this device.

Open timer

Private by architecture

Your beans are not targeting data

Recipes, grinder settings, tasting notes, imports and journal records stay in IndexedDB on this device. Analytics receives only a closed event name and never a recipe value or result.

coffee × ratiowaterrecord + compareone change

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.