An IDX website is any website that receives a feed of fresh listings from your MLS through a third party IDX provider. Generally speaking, third party IDX providers update their MLS listings every 15 minutes. That means that an IDX website will have listings that are just as fresh as your MLS’s website.
Potential buyers will have a very similar experience browsing an IDX website for new listings as your MLS’s site.
While many IDX websites just have listings, others are full agent or brokerage websites that have landing pages, about us pages, mortgage calculators, a blog, videos, and everything else an agent might have on their website.