Short.cm allows you to create short links using your own domain (i.e., www.longlonglonglong.com/morecharacters becomes www.yourdomain.com/euh4F). To make link shortener work you need to have an account in short.cm with any domain. Short.cm is free for accounts with less than 1,000 links and 50,000 requests per month, which is enough for most projects. For $19.99 per month, users can have up to 10,000 links and 3,500,000 redirects per month.
If you would like to build an integration with this tool, check out SharpSpring’s Open API Documentation to see what’s possible.