The feature will only be available when a user is signed in with their Google account and will not affect the way other users receive search results.
The idea is for users to be able to customise searches they may frequently use. For example, if someone searches for cinema listings in their city and they can make a preferred site always come first in the search results -- even if it usually comes further down the list in the natural search.
It also lets users add URLs for sites they would like to show up in the search in future, and to remove results that they are not interested in.
Another feature allows users to make notes on sites, also stored for future searches.
Two of the engineers behind the project, writing on the , said: "The changes you make only affect your own searches. But SearchWiki also is a great way to share your insights with other searchers.
"You can see how the community has collectively edited the search results by clicking on the 'See all notes for this SearchWiki' link."