Add suffix/prefix to URLs, or build URLs from scratch

You will sometimes need to modify URLs in bulk or build them from scratch. There are quite a number of text-manipulation sites out there which are useful for this purpose, such as:
Gilmeister's text tools
TexMechanic's text tools

In the example below, I am building a list of LinkedIn URLs for scraping, starting from just a list of LinkedIn company ID numbers:

There are also ways of doing this with Word, Excel, or advanced text editors such as Notepad++. You can google add suffix each line XXX where XXX is the name of your program. Many useful vids available on YouTube too.