You can’t conduct a search on Google without running into autocomplete — the handy little feature that predicts queries as you’re typing them.
It’s possible you have also seen Google’s autocomplete functionality outside of Google Search, since the autocomplete API can be used by developers on other sites.
Google wants to put an end to how its unrestricted, unofficial and unpublished autocomplete API is being used outside of the core search product.
As Google says, autocomplete was engineered to be used with Google Search, and going forward that’s the only place on the web it will be used.
Google is imposing restrictions on its unpublished autocomplete API, restricting unauthorized access as of August 10th, 2015.
That means developers and publishers will no longer be able to use Google’s autocomplete service on their sites. Autocomplete will only be used as it was intended to be used — in Google search:
“We built autocomplete as a complement to Search, and never intended that it would exist disconnected from the purpose of anticipating user search queries.
We want to ensure that users experience autocomplete as it was designed to be used — as a service closely tied to Search. We believe this provides the best user experience for both services.”
If you had been using Google’s autocomplete API on your site, the company recommends using Google Custom Search Engine on your site instead. That way you can still have autocomplete functionality using a service that’s tied to Google search.