thats not it. you can uncheck china on diablorank and the rankings still differ very much.
my guess is that these two sites dont update all their listed players regularly which results in very different ranks.
Oh, you're right.
Well, then the difference comes from the fact that Diablorank only scans the leaderboards (afaik), so players that got never ranked on any leaderboard in any season are not included in the paragon list. Diabloprogress has been around for much longer, therefore a larger list of profiles; plus, you can manually add battle tags to Diabloprogress that would not show up otherwise. The same is true for Diablo3Ladder by the way. If a character is not on the leaderboards they won't show up in any of those aggregator sites, and since there's not one place where *everyone* registers their account you'll never have 100% matching lists. Also note that those sites not automatically delete the banned accounts. And yeah, the update frequency might not be the same. The API has limits, you can't just scan everything every minute (that's why there are queues if you hit "update" on Diabloprogress/Diablo3Ladder).