(English language and general purpose/web search engines only)
Last updated: 8th October 2016 - Disclaimer: I wrote Mojeek
These search engines crawl the web in order to create their own searchable index of the web.
I made this category up. These also crawl the web but include other engines' results or sometimes just other's.
These engines don't have their own search technology and (usually) pull in results from various sources.
|Bing||https://www.bing.com||USA||Bing||Owned by Microsoft.|
|Exalead||http://search.exalead.com||France||Exalead||Predominantly just a shop window to their enterprise offerings?|
|Gigablast||http://www.gigablast.com||USA||Gigablast||Created and run by Matt Wells.|
|USA||Probably doesn't need any introduction.|
|UK||Mojeek||Created and run by Marc Smith. Only crawler with no tracking?|
|Yandex||https://www.yandex.com||Russia||Yandex||Russia's largest search engine.|
|Entireweb||http://www.entireweb.com/||Sweden||Entireweb + Bing||They have their own crawler and index but also include results from Bing.|
|Qwant||https://www.qwant.com||France||Bing||They crawl the web but their results appear to be provided by Bing.|
|Yahoo||http://search.yahoo.com/||USA||Bing||They still have their own search tech and do limited crawling so maybe one day, although probably not.|
Note: There are hundreds of metasearch engines so this list is not comprehensive and only the most popular are listed here.
|USA||They used to have their own search tech and index, and probably still do, but I never see them crawling.|
|Dogpile||http://www.dogpile.com/||USA||Bing + Google||Long standing. Owned by InfoSpace.|
|DuckDuckGo||https://duckduckgo.com||USA||Bing||Results provided by Bing via Yahoo .|
|Startpage||https://www.startpage.com||NL||They also run Ixquick. Not sure why this isn't as popular as DDG? (Although I do have my own theory.)|
|Unbubble||https://www.unbubble.eu||DE||Various||European search engine with results from Bing, Mojeek, Yandex, and others.|
 It used to be more common for metasearch engines to get their results from various sources, with the presumption it can help to improve relevancy. Now they mostly use Bing and nobody else - although Yandex is increasingly being used. The chances are 99/100 search engines you come across on the Internet will be a metasearch engine, and their results will come from Bing and/or Yandex and not their own index.
 There's a popular misconception that DDG does or has crawled the web, but they never have. This means they don't have access to a full search index or page data and are therefore a Metasearch Engine - also see DuckDuckGo is an odd duck ... for an interesting snippet on their "bot". This is not necessarily a bad thing, it just means they don't have their own search technology and in their current form could not compete with Google or Bing. But allowing people to search a major search engine with an extra layer of privacy is of course still very useful.