- IDX is a set of data approved for public display. API and RETS feeds are different ways of delivering that data. RETS is what most IDX vendors have historically used for their products and continue to use but it is fast becoming outdated technology.
- RETS requires that the vendor download the data from the MLS to the company’s own servers and then push that data into your product. This process results in a delay in the data getting from the MLS to your website. The length of that delay can vary depending on the company. Sometimes it’s as little as every 5-10 minutes and sometimes it’s only once every 12-24 hours. You need to ask your IDX vendor before you sign up, how often data will be updated on your site. The other challenge with RETS is that the data physically leaves the control of the MLS which can be hard to police and monitor. Think of RETS like a fax machine. You put something in at one end and it comes out at the other end but, once that happens, you lose control of that piece of paper and what the recipient does with it.
- API feeds are more like phone calls or Google searches. It’s a constant live feed, with requests coming in from your website straight to the source of the data, your MLS, and then the MLS returning the then-current results for the criteria communicated. There is usually no downloading of data and no delay, resulting in the most accurate results for your website visitors.
NEITHER RETS nor API WILL GIVE YOU A HOME SEARCH EXPERIENCE ON YOUR WEBSITE ON THEIR OWN. These are just data feeds, the engine under the hood of the car. You still need to buy the car (the IDX product) in order for folks to perform a search on your website, or for you to display the listings.