The Forza community maintains a massive car manufacturer color spreadsheet

destructoid.com:

While the most topical discussions about the Forza franchise at large usually have something to do with the latest game’s many fumbles and stumbles, now’s the time to take a look at something different. Did you know that the Forza community maintains a humongous list of real-world car paint specifications?

Indeed, there’s a small, but extremely dedicated community of Forza players that’s spent hundreds, if not thousands of hours meticulously recreating real-world car paint swatches for virtual use. It’s widely accepted that Gran Turismo generally offers a more pleasing and accurate car paint shader, and the fact of the matter is that some of the default manufacturer paints simply don’t match up to their real-world inspiration. These issues have been around since Forza Horizon 4, at least, which is when this community of car paint enthusiasts kicked off their long-lasting project.

Setting aside the incredibly impressive car paint recreation of Gran Turismo 7, it’s a given that many – if not most – players simply won’t care enough about the difference between Ferrari Red and generic red glossy paint. Yet, the issue of correctly replicating the complexity of car paint is a problem for high-tier racing games, and the Forza community decided enough was enough by the time Forza Horizon 4 came out. The problem, at the time, was twofold:

Obviously, there was nothing that players themselves could do about the first part of the problem. As for the second, though… that’s where the incredibly impressive Forza Colour Sheet document comes into the picture.

Featuring a grand total of 10,902 unique real-world paint swatches (as of February 12, 2024) taken from manufacturer libraries, third-party vehicle modders, and various other companies, this document is a testament to one dedicated community’s plight against car paint inaccuracy.

If, for example, you decided that you wanted an almost pixel-perfect British Racing Green Aston Martin in Forza Motorsport, and felt that the