Brewing tool

IBU Calculator

Estimate the bitterness from up to three boil hop additions.

Guide

Before you start

Add your batch volume, boil gravity, and hop additions. Long boils add more bitterness; late additions usually add less.

Calculator

Enter your values

Hop additions

Add at least one boil addition. Use the extra rows if you need them.

Addition 1

Addition 2

Addition 3

Clear

Method

How this is estimated

This uses a Tinseth-style bitterness estimate. Boil time, gravity, hop amount, alpha acid, and batch volume all affect the final IBU.

IBU ≈ utilisation × alpha acid × hop amount ÷ batch volume

Safety and limits

A few notes

IBU estimates always have a bit of wiggle room. This does not model whirlpool hops, dry hops, hop age, kettle shape, or losses.

Use accurate measurements for the best estimate.