IBU Hop Bitterness Calculator
38|Calculate the International Bitterness Units (IBUs) of your homebrew recipe using either the Tinseth or Rager formula. Add as many hop additions as your recipe calls for, enter alpha acid percentages and boil times, and get per-addition and total IBU values plus a BU:GU balance ratio.
39| 40|Hop additions
60| 61|Results
71|Tinseth vs. Rager — which formula should I use?
94|Tinseth is the modern default and is generally considered the most accurate for typical pellet-hop, full-volume boils. It models utilization as a continuous function of time and gravity.
95|Rager tends to predict higher IBU values than Tinseth (often 20–30% higher) and is preferred by some brewers using whole-leaf hops or partial-volume boils.
96|The BU:GU ratio (bitterness units / gravity units) is a balance metric: under 0.5 = malty, 0.5–0.8 = balanced, over 0.8 = hop-forward.
97|BJCP Style IBU Ranges
100|| Style | IBU range | Typical BU:GU |
|---|---|---|
| American Light Lager | 8–12 | 0.30 |
| Helles / Munich Helles | 16–22 | 0.45 |
| Czech Premium Pale Lager | 30–45 | 0.70 |
| Hefeweizen | 8–15 | 0.25 |
| American Pale Ale | 30–50 | 0.75 |
| American IPA | 40–70 | 0.95 |
| Double IPA | 60–100 | 1.10 |
| Stout (Dry Irish) | 25–45 | 0.85 |
| Imperial Stout | 50–90 | 0.75 |
| Saison | 20–35 | 0.50 |
| Belgian Tripel | 20–40 | 0.40 |
| Barleywine (American) | 50–100 | 0.85 |