AeroPress Coffee Ratio: 1:12 to 1:18 by Density

Updated October 2026 · AeroPress Recipe Series

The ratio sets the strength of your finished cup. In the AeroPress Recipe Series it changes with the density of your roasted beans, across all 121 recipes.

The short answer

1:12 for the darkest roasts, 1:18 for the lightest, and 1:15 in the middle (Recipe 61, 0.390 g/ml). It is the same scale as the Filter and French Press series, and the recipe works out the dose and brew water for you.

The range Why 1:15 in the middle References

How the ratio is measured

Measured against the finished cup

The AeroPress Recipe Series quotes the ratio against the finished cup, which is the strength you actually drink. The AeroPress gets there differently from other methods: you brew a concentrate, press it, then top it up with water to the cup weight.

The dose is bigger than the ratio suggests

The recipe shows the dose and brew water for you.

You brew with little water, and the puck holds back part of the concentrate, so the dose you weigh is larger than the cup weight divided by the ratio. See the AeroPress dose guide.

The cup weight is fixed

Every recipe finishes at the same cup weight, shown on the recipe, so the ratio changes the strength of the cup and not its size.

The range

The range: 1:12 to 1:18

The ratio rises in a straight line with density, 0.05 per recipe, from 1:12 at 0.330 g/ml to 1:18 at 0.450 g/ml, and the recipe shows it to the nearest whole number.

1:12

0.330 g/ml, the darkest roasts (Recipe 1)

1:15

0.390 g/ml, the middle (Recipe 61)

1:18

0.450 g/ml, the lightest roasts (Recipe 121)

And in between:

1:13

Recipe 21

1:14

Recipe 41

1:16

Recipe 81

1:17

Recipe 101

Find your recipe

Why this range

Why the ratio changes with roast level

The ratio is your most powerful lever on how much dissolves. In the series, each end of the range is matched to the roast that needs it.

Dark roast · 1:12

Dark roasts are brittle and give up their solubles easily. Less water per gram keeps extraction, and bitterness, in check, and the stronger cup stands up to the roast.

Light roast · 1:18

Light roasts are dense and resist extraction. More water per gram extracts more, so they taste sweet and clear rather than sour.

The same logic as espresso, filter and French press

It’s the same principle as the espresso ratio, the filter ratio and the French press ratio: water is the solvent, and ratio is your most powerful lever. A fixed ratio for every coffee means dark roasts come out bitter and light roasts sour.

The midpoint

Why the midpoint is 1:15

Recipe 61, at 0.390 g/ml, is the middle of the series, and its ratio is 1:15.

The same scale as Filter and French press

All three series run from 1:12 to 1:18 with 1:15 in the middle. Filter measures the coffee in the cup, French press the water you pour, and AeroPress the finished cup after the top-up.

Concentrate, then top up

Many World AeroPress Championship recipes brew a concentrate and then dilute it, and the series follows that approach. The concentrate ratio on each recipe runs from about 1:3 for the darkest roasts to 1:6 for the lightest.

Time stays fixed

Every recipe steeps for one minute, so the ratio, dose, grind and temperature do the work of matching the brew to your roast.

Where to start

Haven’t measured your beans? Start at Recipe 51 (0.380 g/ml), then use Extract More or Extract Less. Measured? The coffee density calculator takes you straight to your recipe.

References