If you've looked around in your stats page much, you've probably noticed a percentage number for each game type that says 'percentile.' What does that mean?
Percentile is a term used in statistics to describe the percentage of a group that falls at or below a certain level. The measure in this case, is the person's rating.
In the above picture, the member is at the 42nd percentile. The percentile number here means that 42.7% of members on Chess.com have a rating that is equal to, or below this member's rating.
For a clearer example, Hikaru's blitz percentile is 100%, because 100% of everyone on Chess.com has a blitz rating equal to, or below Hikaru's rating!
The important thing to remember is that this number is describing the percentage of members who are equal to or below the person's rating. Hikaru is at 100% because no one is higher than his rating. This puts 100% of everyone at equal to, or below him.
Another way to think of the percentile is as the percent of people on Chess.com who you are better than!
Why can't I see my percentile?
If your percentile isn't showing, or is showing N/A this may be because you have a new account, or because you haven't played any of that game type recently.
In order to appear on leaderboards and have your percentile calculated, your account must be at least 7 days old.
You also must have played 20 games of that game-type, with the most recent game being in the past 90 days. If you go 90 days without playing a blitz game, for example, you will no longer be able to see your blitz percentile until you play at least one blitz game.
Your account must not be closed or muted. If your account gets muted you will temporarily be removed from leaderboards and won't be able to see your percentile, though you will return when your mute expires. Closed accounts do not appear on leaderboards and cannot see their percentile.