regex for number of characters code example

Example 1: regex for number and letters

let regex = /[^A-Za-z0-9]+/

Example 2: regex for counting characters

( *?[0-9a-zA-Z] *?){10,}

Example 3: numbered occurences in regex

/^[a-z]{0,10}$/

{3} exactly 3
{6,} at least 6
{2,5} 2 to 5