Measure final gravity (FG)
A final gravity (FG) reading lets you know how much of the available sugar in the original wort has been consumed by the yeast. Typical readings for some styles are given below.
| Beer style | Typical final gravity |
| Lite American lager | 0.998–1.008 |
| Irish stout | 1.007–1.011 |
| American IPA | 1.010–1.018 |
| American barleywine | 1.016–1.030 |
To estimate your beer's alcohol content, subtract the original gravity from the final gravity and multiply by 131.25.
ABV = 131.25 × (OG − FG)
For our CB&B Pale Ale, with estimated OG and FG of 1.053 and 1.013, respectively, that means we expect about 5.3 percent alcohol by volume:
ABV = 131.25 × (1.053 − 1.013) = 5.3%