Short.io allows you to create short links using your own domain (e.g www.longlonglonglong.com/morecharacters becomes www.yourdomain.com/euh4F)To make link shortener work you need to have an account in Short.io with any domain. After installing the Short.io Slack app, you can create short links by simply writing /shorten http://longlonglong.com/long and service will respond with a short URLShort.io is free for accounts with less than 1000 links and 50 000 requests per month, which is enough for most of the projects. For $20 per month you can have up to 10 000 links and unlimited redirects per month