This service will be shutting down on October 20th. Thanks for using it!
It has served its purpose as a restricted way to display the recipes. The website contacts a server that I am running to calculate the recipes, which was done in order to try and hide the PRNG algorithm until the developers were okay with it being shared.
Now that the embargo is over, there are better ways to get this information.
Personally I recommend Pyry's great cheatgui mod, which displays this information ingame.
For an offline tool, you can use Saphire's noita_unicorn tool.
If you want to see the source code that the server is running, you can check it out here. Feel free to rewrite it in JS and put it up on your own website!
Huge thanks to Saphire for the work on the recipe algorithm as well.
(06.10.2019) EXPERIMENT: I discovered that one of two random numbers that I previously didn't know the purpose of are used in the 'probability' field of a reaction. I'm not sure whether this means the probability of these elements turning into the target or the probability of them just disappearing without doing anything, but I thought it might be useful to include this in the site. As this is very fresh, it might be inaccurate.
There are currently only two materials in the game that are hardcoded to be random (based on the world seed) - Lively Connoction and Alchemic Precursor. This site was made using reverse engineered knowledge. It uses the exact same algorithm that the game uses to generate the lists of ingredients necessary.
Actual algorithm mostly by @Saphire, some help by me. Website & infrastructure by me.
NOTE: There is still a very small chance that the rewritten algorithm isn't 100% correct. Please report any inaccuracies to @Zatherz and they will be fixed ASAP.
NOTE: There was a reported inaccuracy with Ster's playthrough. This has turned out to be nothing more than just the wrong seed being used, therefore there are currently no confirmed inaccuracies with this algorithm that are not results of incorrect usage.
Publicized with permission.