Brewing Calculation · Batch planning

Coffee Dose Calculator

Set the number of servings and your cup size, pick a brewing method for a sensible default ratio, and the calculator returns the dose, the brew water and a weekly bean consumption estimate.

Tool

Servings

Cup size (ml)

Brewing method

Ratio 1 : X

How It Works

Most recipes give a dose and a water weight, but the real question at breakfast is how much coffee two full mugs need. The calculator inverts the usual formula: it starts from the beverage volume you want in the cup and works backwards through water retention to a dry dose, using dose = beverage ÷ (ratio − retention).

Retention is set at two grams of liquid per gram of grounds for filter and immersion brewing, and zero for espresso where the puck stays in the basket and the yield is measured directly. Selecting a method loads a typical ratio for that device — tighter for immersion brewing, wider for cold brew concentrate — which you can override at any time. The weekly figure simply multiplies a single daily brew by seven, which is a practical way to judge whether a 250 g bag will last.

Step-by-Step Usage Guide

Enter how many cups you need and the volume of the mug you actually drink from.
Pick the brewing method so a suitable default ratio loads automatically.
Adjust the ratio if you prefer a stronger or lighter cup than the default.
Weigh the calculated dose before grinding, and pour the calculated water — not the cup volume.
Use the weekly estimate to plan bag sizes so beans are finished inside their freshness window.

Frequently Asked Questions

Why is the brew water larger than my cup volume?+

Because the coffee bed keeps about two grams of water per gram of grounds. Pouring only the cup volume would leave you noticeably short.

Can I scale one recipe up to eight cups?+

Up to about four cups, scaling is close to linear. Beyond that, bed depth and drawdown change, so grind slightly coarser and expect a longer brew time.

What cup size should I use?+

Measure it. A 'cup' ranges from 120 ml in a small ceramic to 350 ml in a travel mug, and that difference is larger than most recipe adjustments.

How does this apply to espresso?+

For espresso, treat the cup size as the beverage yield in grams and set the ratio between 1.5 and 3. The Espresso Parameter Calculator handles this case in more detail.

Applicable Scenarios

This is the planning tool for households: brewing for guests, sizing a weekend batch, budgeting a monthly bean subscription, or packing the right amount of coffee for a trip. It also helps anyone who has just moved from a small dripper to a larger one and needs to rescale a familiar recipe without guesswork.