Today's Rank: #20577 of 49,070 (58.1%)

On my online chess it says this under where my best win is

Does anyone know what this means?

it means you're the 20,577th highest rated player out of the 49,070 active players on chess.com; it also says that 58.1% of the players are below you in rating.

# is your actual rank

'# of' your rank out of total players

The % is the number of people you are ranked higher than.

Oh ok thanks for help!