RSS Lookup is a free, open-source tool designed to find the RSS feed associated with any URL

https://github.com/mratmeyer/rsslookup

RSS Lookup is a free, open-source tool designed to find the RSS feed associated with any URL. Simply paste the website's address, and RSS Lookup will scan the site's HTML and check common feed path conventions to give you the best chance at finding feeds on the site.

Check out the live tool: www.rsslookup.com