> For the complete documentation index, see [llms.txt](https://docs.rapt.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rapt.io/tools/abv-calculator.md).

# ABV Calculator

The ABV Calculator estimates the resulting alcohol by volume from original and final gravity values.

The calculator uses the simple conversion formula:

```
ABV = (OG - FG) x 131.25
```

Note that due to the manner in which the RAPT Portal calculator handles rounding of decimals, the calculated gravity may differ from this calculator