Hop Calculations.

IBU Calculator     Hop Weight Calculator (for a required level of IBUs)     Replacement Hop Calculator (for hops of different AA% content)

The level of bitterness of a beer is calculated in IBUs (international bittering units) also known as EBUs (European bittering units).

Individual varieties of hop have provide different levels of bitterness per unit of weight, this  is measured by Alpha Acid content. Same varieties also vary from year to year.

Utilization is a way of measuring the extraction of bitterness from the hops in a recipe. 

Utilization varies with the vigor of the boil, the volume of the boil, the gravity of the boil and the duration of the boil.

After a typical boil duration of 90 mins, utilization will be around 30% for a low gravity (1030) wort and around 23% for a high gravity (1060 wort).

After a boil duration of 60 mins, utilization will only be slightly less at around 28% for a low gravity (1030) wort and around 21% for a high gravity (1060 wort).

For an average gravity wort  utilization will be around 27% during a 90 min boil and around 25% for a 60 min boil. These figures can be adjusted with experience and should be only used as a guide..

Use this calculator to estimate the IBUs (or bitterness) of a particular recipe. 
(if more than one hop is used or multiple additions are used then calculate the hop additions separately then add the results together to give total IBUs)


Bitterness (IBU/EBU) Calculator

Enter Weight of Hops: grams
Enter Alpha Acid Content of Hops: %
Enter Estimated Utilization: %
Enter Volume of Batch): L

Click to Calculate Bitterness of Hop Addition

Bitterness: IBUs (aka EBUs)


Stronger, higher gravity beers require a higher level of bitterness to balance out the sweet malt flavours.

When designing a recipe a rule of thumb is that IBUs/OG should equal 1 or less to avoid excessive bitterness.

Use this calculator to work out the weight of hops required to in a recipe to produce a desired level of IBUs.


Hop Weight Calculator (for a required level of IBUs)

Enter Required IBUs:
Enter Alpha Acid Content of Hops: %
Enter Estimated Utilization: %
Enter Volume of Batch): L

Click to Calculate Weight of Hops

Weight of hops required: grams


If a particular hop isn't available or a replacement hop is to be used in a recipe, the weight of hops should be adjusted to allow for different alpha acid contents.

Use the following calculator to determine the the weight of a replacement or substitute hop required.


Calculate the Weight of a Replacement Hop

(with a different alpha acid content)

Enter Original Weight of Hops in Recipe: grams
Enter Alpha Acid Content of the Hops Used in Recipe: %
Enter Alpha Acid Content of New or Substitute Hops: %

Click to Calculate Weight of New Hops Required:

Weight of hops required: grams


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