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Recipe

Hop substitution

Your Magnum at 12% replaced by a hop at 10%: you need 20% more. The tool gives the exact weight.

Greater than 0.

Result

Fill in the values and run the calculation, or try the example.

This is the calculation Krausi uses. Create an account to save it in a recipe or a brew.

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Why recalculate the weight of a hop?

Every bag of hops carries its own alpha acid content, which varies with the variety, the harvest and the grower. The same recipe, with the same weight of hops, changes bitterness from one brew to the next if you do not pay attention.

The calculation is used in two situations: your usual hop has a different content from the recipe's, or it is out of stock and you replace it with another variety. In both cases, you adjust the weight to bring the same amount of alpha acids.

How is the substitute weight calculated?

The weight is corrected by the ratio of the alpha acid contents:

substitute weight = original weight × original alpha / substitute alpha

For aroma, choose a similar variety. A few classic swaps: Cascade and Centennial, Saaz and Sterling, Magnum and Nugget for bittering, Citra and Mosaic for tropical fruit.

Worked example

Values entered

  • Weight of the original hop in g: 30
  • Alpha acids of the original hop in %: 12
  • Alpha acids of the substitute in %: 10

Result from the tool

Weight of the substitute in g
36 g

What the tool does not do

  • The calculation keeps the bitterness, not the aroma: two hops with the same alpha content can smell very different.
  • It applies mostly to bittering additions early in the boil.
  • An old hop has lost part of its alpha acids: the content on the label is then overstated.

Frequently asked questions

What can I replace Citra with?

Mosaic, Simcoe or Galaxy give similar fruity, tropical aromas. Adjust the weight to the substitute's alpha acid content for boil additions.

My hops have lost alpha with age, what should I do?

Hops kept vacuum-packed in the freezer lose little. At room temperature, expect a loss of 20 to 40% in a year: increase the weight accordingly for bittering additions.

And with the assistant?

Ask Krausi the same question in plain language: he picks this tool, does the calculation and files the result in your project.

The recipe calls for 30 g of Magnum at 12%, my bag is at 10%.

Use 36 g of your Magnum at 10% to keep the same bitterness. I've corrected the quantity and the alpha acid content in the recipe.

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