It doesn't really have a top. Assuming that the top is now as it was a couple of years ago, 5.14, someone will eventually "send" a route which will end up being ranked higher than 5.14 by concensus. Once you get up past 5.12 they started adding letters. Ex: 5.12a is easier than 5.12c. Its not very precise. I would also say its not smoothly linear. Meaning the diff between 5.12 and 5.14 is not linear. Its probably not exactly exponential either. Now, you are probably saying "What a bullshit system." and you'd be right. But that's how it works. https://en.wikipedia.org/wiki/Yosemite_Decimal_System Once you think you have it, I'll throw another variable into the mix. A 5.12 in a plastic gym in California is not the same as a 5.12 in Yosemite National Park is not the same as a 5.12 in The Red River Gorge. /shrug