Up the IBU

[skeaterbait]

I hope this is the right place for this; I am getting some wort from someone for a contest, we are to take the wort, give it our own flair. It's come in at 12.4 IBU and I would like to bring that up a bit to a bit over 20. I figure on doing this either by dry hopping or perhaps a hop tea.

My question is, how do I know how much hops to add? I am drastically impaired when it comes to math so I am really hoping for a chart or simple formula for this.

 

[Ostomo517]

If you know the recipe for this wort you can put it all into Beersmith or a app like Brewr and work from there but fyi dry hop will give you little to no actual IBUs