Do More Web & Search Search the Invisible Web: 20 Free Resources Expand your searches to these deep web resources Share Pin Email Print Matt Brown / Flickr / CC BY 2.0 Web & Search Search Engines Best of the Web Safety & Privacy Running a Website by Tim Fisher Tim Fisher has 30+ years' professional technology support experience. He writes troubleshooting content and is the General Manager of Lifewire. Updated August 27, 2019 129 129 people found this article helpful When you access the invisible/deep web, you're uncovering information a regular search engine won't find. This is because data on the invisible web isn't made available to software spiders and crawlers that create search engine indexes. Given that the invisible web makes up a huge majority of the content on the web, it's fair to say that you're missing out on quite a lot if you never venture away from popular search engines like Google and Bing. Below are 20 invisible web search engines, directories, and databases that you can use to uncover an astounding amount of content. The invisible web is only part of the web that common search engines don't catalog. The other portion, called the dark web, is often associated with illegal activities. 01 of 20 Wayback Machine What We Like Lots of content. Displays most pages perfectly. Easy-to-understand results. Keeps you on the site while browsing. What We Don't Like Keyboard shortcuts would be helpful but aren't supported. Iffy keyword search. Not all sites are archived. Our Review of Wayback Machine The Wayback Machine is a deep web tool that holds a vast number of web pages, over 300 billion, in fact. As part of the nonprofit Internet Archive, the Wayback Machine has decades of web pages archived and accessible to anyone. Not only are websites stored there but also books, audio recordings, concerts, videos, television news programs, images, and thousands of software programs. Visit Wayback Machine 02 of 20 USA.gov What We Like Accurately categorized results. Government web pages only. Ad-free. What We Don't Like Basic search is overwhelming. Lacks advanced search options like filtering. Another invisible web searcher is available at USA.gov — a mammoth search engine and portal that gives you direct access to a wide variety of information and databases from the U.S. government, state governments, and local governments. USA.gov includes access to the Library of Congress, an A-Z government agency index, the Smithsonian, and much more. Visit USA.gov 03 of 20 The WWW Virtual Library What We Like Easy-to-use, simple design. Curated links. What We Don't Like Many links are dead. Supports only a few languages. Dull user interface. Pages haven't been updated since early 2017. The WWW Virtual Library includes hundreds of different categories and databases on a wide variety of subjects, ranging from agriculture to international affairs. The site claims that the WWW Virtual Library is the oldest catalog of the web, started by Tim Berners-Lee, the creator of HTML and of the World Wide Web itself, in 1991 at CERN in Geneva. The website is run by volunteers who compile pages of links for particular areas in which they have expertise. The Virtual Library's deep web pages are among the highest-quality guides to specific sections of the web. Visit The WWW Virtual Library 04 of 20 Science.gov What We Like Queries millions of pages. Advanced search feature. Lots of filtering options. Results can be emailed. What We Don't Like Results seem cluttered. Some search results are only contact information. Science.gov searches over 60 databases and more than 2,200 selected websites from 15 federal agencies, offering 200 million pages of authoritative U.S. government science information, including research and development results. The Science.gov website is an interagency initiative of several U.S. government science organizations. These agencies form the voluntary Science.gov alliance, which governs the site. Visit Science.gov 05 of 20 Wolfram Alpha What We Like Covers lots of material. Very detailed results. Suggests searches as you type. Mobile apps. What We Don't Like Not all features are free. Can be overwhelming. Wolfram Alpha is a computational deep web search engine, which means it stores a vast amount of pure data available to you by search and by a question-and-answer format. The website aims to collect and curate all objective data; implement every known model, method, and algorithm; and make it possible to compute whatever can be computed about anything. Visit Wolfram Alpha 06 of 20 The National Security Archive What We Like Advanced search capabilities. Easy-to-read synopses. Thousands of documents. What We Don't Like Can't change how the results are sorted. Cluttered home page could be overwhelming. The National Security Archive at George Washington University is another free invisible web search tool that's home to a treasure trove of declassified documents, papers, and other primary-source materials on subjects related to U.S. national security, foreign policy, intelligence policy, and diplomatic and military history. The site was founded in 1985 and is home to decades worth of documents released under the Freedom of Information Act. Visit The National Security Archive 07 of 20 Alexa What We Like Free trial. Self-explanatory. Lots of data. Browser extension support. What We Don't Like Many tools aren't available for free. No site map, search, or FAQ page. Alexa provides analytical information about web properties that's so specific that no regular search engine can compile it. The service gathers much of its traffic data from direct sources in the form of sites that chose to install the Alexa script to certify their metrics. The traffic estimates on Alexa are based on data from a global traffic panel, which is a sample of millions of internet users using one of thousands of different browser extensions. Website owners especially can benefit from the data that Alexa offers; for example, here's a list of the top 500 sites on the web. Visit Alexa 08 of 20 Directory of Open Access Journals What We Like All the content is free. Abstract and full text. Lots of filtering options. Supports translations. What We Don't Like Results lack a preview. Not all journals have applied and some have been removed from the site. The Directory of Open Access Journals (DOAJ) is an invisible web resource that indexes and provides access to quality open access, peer-reviewed journals. Thousands of journals and millions of articles are searchable using the DOAJ. The Directory of Open Access Journals indexes research journals, periodicals, and their articles' metadata. The DOAJ aims to be comprehensive and cover all open access scientific and scholarly journals that use an appropriate quality control system. The directory's goal is to increase the visibility and ease of use of open-access scientific and scholarly journals — regardless of size and country of origin. Visit Directory of Open Access Journals 09 of 20 The Online Books Page What We Like No ads. Lots of ways to browse. Variety of free content. What We Don't Like Bland website design. Lacks advanced filtering and searching. The Online Books Page, a deep web service offered by the University of Pennsylvania, gives readers access to more than two million books freely accessible (and readable) on the internet. Visitors also gain access to significant directories and archives of online texts, as well as special exhibits of particularly interesting classes of online books. Visit The Online Books Page 10 of 20 The Library of Congress What We Like Trending searches page. Lots of filtering options. Search term suggestions. Different viewing options. Sorting capabilities. What We Don't Like Results often refer to documents only available in person. All connections may be in use at peak times, interfering with search. One of the most vivid and interactive sites on this list of invisible web resources, the Library of Congress offers an incredibly rich and varied array of content. Collection highlights include congressional records, digital preservation resources, the Veterans History Project, and the World Digital Library. According to the site: The Library of Congress is the nation's oldest federal cultural institution and serves as the research arm of Congress. It is also the largest library in the world, with millions of books, recordings, photographs, maps and manuscripts in its collections. Visit The Library of Congress 11 of 20 Census.gov What We Like Helpful visuals. Data finding tools and apps. Variety of search term suggestions. What We Don't Like Overwhelming amount of information. News and press releases mixed with data results. If you're looking for data not found in your typical search engine, Census.gov is one of the first places you'll want to visit. From geography to population statistics, you'll be able to find them on this website. The U.S. Census Bureau conducts demographic, economic, and geographic studies and strengthens statistical development around the world through technical assistance, training, and software products. For decades, the Census Bureau has performed international analytical work and assisted in the collection, processing, analysis, dissemination, and use of statistics with counterpart governments in over 100 countries. Visit Census.gov 12 of 20 Copyright.gov What We Like Basic and advanced search tool. Hints on how to make searches. What We Don't Like Not very user-friendly. Finding the correct search option is challenging. Copyright.gov is another U.S. government resource you can put in your invisible web search toolbox. Here, you can view works registered and documents recorded by the U.S. Copyright Office since January 1, 1978, as well as search records of registered books, music, art, periodicals, and other works, including copyright ownership documents. Visit Copyright.gov 13 of 20 Catalog of U.S. Government Publications What We Like Updates daily. Hundreds of thousands of results. Manually browse pages. What We Don't Like Outdated page functions. Navigation is not intuitive. The Catalog of U.S. Government Publications gives deep web surfers instant access to electronic and print publications from the legislative, executive, and judicial branches of the U.S. government, with more than 500,000 records generated since July 1976. Visit Catalog of U.S. Government Publications 14 of 20 PubMed What We Like Huge trove of data. Data exporting capabilities. Simple and advanced search options. What We Don't Like Unfriendly interface; can be hard to use. Overwhelming amount of results. PubMed, part of the National Center for Biotechnology Information, U.S. National Library of Medicine, is the perfect invisible web resource for anyone who's looking up medical or medical-related information. It offers more than 29 million citations for biomedical literature from MEDLINE, life science journals, and online books. Visit PubMed 15 of 20 FAA Data & Research What We Like Modern interface. Official, always up-to-date data. Clear and understandable menu headings. What We Don't Like No advanced search options. No FAQs. The FAA Data and Research pages offer information on how FAA research is done, the resulting data and statistics, and information on funding and grant data. Anything from aviation safety to unruly passengers (seriously) can be found here. Visit FAA Data & Research 16 of 20 DuckDuckGo What We Like Privacy-conscious. Forces site encryption. Mobile apps. Sorting and filtering options. What We Don't Like No easy-to-use advanced search box. No date information in search results. 10 Things That Might Surprise You About DuckDuckGo DuckDuckGo searches both the regular web and the deep web without saving any of your personal information or your search results. DuckDuckGo blocks advertising trackers to keep your search history private. Although DuckDuckGo resembles other search engines — and a simple one at that — it's fully capable of performing advanced searches on the deep web. Visit DuckDuckGo 17 of 20 FindLaw What We Like Great learning resource. Very comprehensive. Easy to use. Several filtering options. What We Don't Like Lots of ads. Primarily a service referral site. FindLaw is a gigantic repository of free legal information on the internet, and it offers one of the largest online lawyer directories available. You can use FindLaw to locate an attorney, learn more about U.S. law and legal topics, and participate in the active FindLaw community forums. Visit FindLaw 18 of 20 The Louvre What We Like Simple website. A few sorting options. What We Don't Like Displays advertising. Too simple of a search tool. The online Louvre museum begs to be discovered and cherished by art lovers all over the world. View thematic collections of art, get more information about the background of selected works and view art aligned with historical events. Visit The Louvre 19 of 20 Economy.com's Indicators What We Like Continuously updated. Clear and concise data. Lots of information. Region-specific. What We Don't Like Poor search tool. Unintuitive interface. Economic Indicators on Economy.com gives users quick access to free economic, demographic, and financial data. It provides comprehensive and extensive historical and forecasts data at the national and subnational-regional levels representing over 93 percent of global GDP. Economy.com's Indicators covers more than 180 countries, over 150 global metro areas, and all U.S. states, metro areas, and counties. The databases contain economic, financial, demographic, and consumer credit time series. Visit Economy.com's Indicators 20 of 20 Bankrate What We Like Wealth of information. Extremely user-friendly. Free calculators. Useful sorting options. What We Don't Like Too simple of a search tool. Lots of ads. Bankrate, an online financial resource that's been around since 1996, offers a huge deep web library of financial information on current interest rates, mortgage lender reviews, ARMs, articles on CUSIP, and much more. Visit Bankrate Continue Reading