How to get count of users having each role, as well as the count of all users?

By default WordPress having an function called count_users() to get count of users having each role, as well as the count of all users.
Check below example code for your reference.

$result = count_users();
echo 'There are ', $result['total_users'], ' total users';
foreach($result['avail_roles'] as $role => $count)
    echo ', ', $count, ' are ', $role, 's';
echo '.';

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