Pretty big behind-the-scenes update: I've updated the calculator to use the
complete BW damage formula, so everything should now be 100% accurate to the actual cartridges, down to the last point of damage. I had to rewrite a lot of the code, which means it's possible some new typos slipped in there, so let me know if you see anything wonky in your calcs! Huge thanks to Xfr, Bond697, Kaphotics, and V4Victini for their work researching the damage formula and explaining it so thoroughly.
In a slightly more visible change, I also took the opportunity to add a few new variables, particularly for 2v2 players. Damage reduction for spread moves in doubles, Reflect/Light Screen's reduced effectiveness in doubles, Helping Hand, critical hits, and a couple other things that I can't recall at the moment have been added to the equation.