What do comma separated numbers in curly braces at the end of a regex mean?

Question

I am trying to understand the following regex, I understand the initial part but I\'m not able to figure out what {3,19} is doing here:

/[A-Z][A-Za-z0-9\\s]{         


        

Answer 1

The regular expression you have there /[A-Z][A-Za-z0-9\s]{3,19}$/ breaks up to mean this:

[A-Z] We are looking for a Capital letter

Followed by

[A-Za-z0-9\s]{3,19} a series of letters, digits, or white space that is between 3 and 19 characters

$ Then the end of the line.