JEI with a built-in calculator

This is and likely forever will be my favorite recipe mod, and it should be yours too.
Compatible with JEI, almost all JEI plugins, and most add-ons (though in my experience the alternatives built for EMI tend to work better with it) this is a true drop-in replacement.
If the modpack you're playing doesn't already have it installed, you likely can simply add it to your mod-list to get the full experience.

So, why switch?
Aside from there being no reason not to given the aforementioned compatibility.
The main feature is the crafting tree, it's like a crafting calculator that you can easily customize, reads your inventory and the inventory of your chest, and will help you semi-auto-craft your pinned item(s).
I'll include an image of an example crafting tree for the Dimensional Seed from ATM9, keep in mind that Very Large recipes can cause some lag and start eating up your ram, however, I'm able to view the recipe for the ATM star from the same pack without issue, tho a screenshot would be pointless because it barely fits.

Additionally, it offers so much customization, while the standard layout will look familiar to all modded mc players, you can change the multiple panels to appear wherever you want, personally, I like to keep my "craftables" always available under my favorites.

There are a few features I miss from REI such as drag and drop, and recipe cards, other features like favoriting specific recipes and easy craftables toggles are present. However, it's very possible I simply missed these options. While the config is clean and navigable, even I still find it overwhelming and there are to this day features I've seen others use that I don't know how to access, really this is my primary critique, I'd almost like a sort of tutorial if I'm being honest, but for a utility all about customization and qol, I don't think having too many features/config options should detract any points in a review.

While the average player will likely never know or care, I also want to appreciate the customization options when it comes to resource packs. I've maintained a UI resource pack (Overgrown Flowery GUI) and overhauled all three major recipe viewer mods, and EMI was easiest to work with and gave plenty of space for customization, overall I like the look of EMI the best with or without a resource pack.