Get users order by meta key with limit

by

You can use get_users() with meta_key and order by meta value, descending.

Example:

$user_args = array(
    'meta_key' => 'points',
    'number' => 10,
    'orderby' => 'meta_value_num',
    'order' => 'DESC'
);

$top_users = get_users($user_args);

NOTE: Support for meta_value_num is available only from version 4.2