This pattern will match everything directly below your yahoo REPLACE section and non of the good cases above: ^yahoo\.com?(?:(?!\.[a-z]{2}).)*(?:.com?)?$ IE you do not want to include yahoo.fr or yahoo.com.fr or yahoo.co.uk

Used for replace characters on keyup in javascript: $(document).on("keyup", ".input", function(e) { var target = $(e.target); var value = target.val(); target.val(value.replace(/^-*\.+$||^\.+(?!$)|^0+(?=[0-9]+)|\.(?=\.|.+\.)|(?!^)-/g, '')); });...

Номер телефона без "8" в первой позиции кода региона . +7 (926) 255 - 55 -55 можно, а +7 (826) 255 - 55 - 55 нельзя

Regex for date in ISO 8601 format that also check the number of day in a month to be sure the date is valid