Coffee Calculators
Moka Pot Capacity Calculator
https://www.coffeesizing.com/calculators/moka-pot-capacity/
Estimate only — not a cupping score, a water lab or a roast profile. Confirm on a test brew.
Moka Pot Capacity Calculator
A moka pot is not espresso, but it still wants a brew ratio. Fill the basket without tamping like a portafilter, leave the safety valve clear in the boiler, and weigh once so ‘6-cup’ means grams, not marketing. Fill fraction keeps you off a packed dry puck and a flooded valve.
Inputs
Results
- Coffee dose
- 21.6g
- Water
- 180.0g
- Brew ratio
- 8.33
Water mass per gram of coffee. Moka often lands tighter than V60, looser than espresso.
Recommended gear
Bialetti Moka Express
Measure your actual basket and boiler; ‘6 cup’ is a nickname. This calculator wants millilitres you poured.
Typical range: $25–$50
0.1 g coffee scale
Confirm doseG against the 0.45 g/ml guess. Your grind size changes how much fits a level basket.
Typical range: $20–$80
1Zpresso K-Ultra
Moka wants finer than filter, coarser than espresso. A repeatable mill stops the sputtering bitterness.
Typical range: $80–$250
Calculation method
Dose assumes a loose bulk density around 0.40 g/ml times basket volume times fill fraction (mid of the ~0.3 dark to ~0.5 light range). Water is chamber millilitres times the same fraction (grams ≈ millilitres). Ratio is water over dose — a 60 ml basket and 200 ml boiler at 0.9 fill is about 21.6 g coffee and 180 g water, near 1:8.3. That is why moka tastes stronger than a 1:16 V60 and is still not a 1:2 shot.
Exact formula
doseG = basketVolumeMl × fillFraction × 0.40. waterG = waterChamberMl × fillFraction. ratio = waterG / doseG. Limits: Grind, heat and the steam-driven extraction omitted; 0.40 g/ml is untamped medium bulk density, not espresso tamp density.
Valve safety
The fill fraction on the boiler is also a safety number. Covering the valve is how moka pots become projectiles. Stay below it even if the calculator would allow 1.0.
Not espresso
You will not get 9 bar or a 1:2 yield. If you want espresso ratios, use a machine and the dosing calculator. Moka is its own brew ratio.
Frequently asked questions
Should I tamp?
No. A moka basket is not a portafilter. Level the bed; tamping plus a fine grind is how you get a sputtering bitter geyser.
Pre-heat the water?
Many people fill with hot water to shorten the time the grounds sit baking. The masses do not change; the flavour might.
Why 0.40 g/ml?
It is a typical un-tamped medium-fine bulk density. Dark roasts pack lighter, light denser. Weigh your filled basket once and you can ignore the constant forever.
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