Giseldah of the LOTRO Forums (AKA Math Whiz Extraordinaire) has taken their excel version of the ratings calculator and made it in to a web format.
Visit the original post about it here: LOTRO Ratings Calculator
The original version is not web hosted, so you need to download files to your computer and then view it via a web file.
I have spoken with Giseldah and they have agreed to allow me to host the files to make it easier for everyone.
Select your class, level, difficulty, and stat you want to analyze from the top drop down menus (pictures).
Fill in the white boxes of the left hand column with the rating (number). click the lock icon and then the –> % column will populate with your current % rating.
The white boxes in the Rating % column will auto populate to the stat cap for the level and difficulty you chose at the beginning. If you want to find out what you need to get to a percent below the cap that just enter the percent manually.
The –> # and Diff # columns will auto populate. The –> # is telling you how much the cap % is as a rating (ex. Crit cap of 25% = 630,000 crit).
The Diff # is telling you how much you need to add to get to cap (ex. add 10,000 more finesse to get to the cap of 50%).
NOTE 1: It cannot account for class bonuses you may get from traits. You need to manually add this % to those that show in the Calculator.
NOTE 2: While this tool displays the stat caps, it is impossible for anyone to actually reach the cap for all stats simultaneously. You will need to decide what is most important for your class and play style and work from there.
Ex. A support Lore-master (yellow line) will want to get their finesse up quite high (in the 340,000+) range at 130 for T5 difficulty content. This is not the cap of 630,000 and nor does it need to be.
This is an excellent tool to find out how much of a stat you need to reach your goal such that you can plan your gear accordingly. It is especially useful of you have a selection box with items in it and you are not sure what to choose. You can enter the numbers in to the boxes and the math is done for you.
A huge thanks to Giseldah for all their work !!