Locating Archived Information & Data
There are a number of approaches to locating archived data. If you know what type of information (subject, source, etc.) that you're looking for, then you can go directly to one of the subject-focused resources on this page. If you're unsure of where the data might have originated, you can search the more general and/or comprehensive resources. And if you want to look at data from a specific source at a specific time, you can use the resources and techniques listed here.
See our datasets guide for more resources beyond archived data.
Search Engines and Aggregators of Archived Data
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Wayback MachineMaintained by the Internet Archive, you can search the Wayback Machine for specific URLs or specific collections of archived data.
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Archive-ItUse Archive-It to collect and access worldwide cultural heritage on the web.
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Harvard Law School Innovation LabHarvard Law School Library Innovation Lab has created a data vault to download, sign as authentic, and make available copies of public government data that is most valuable to researchers, scholars, civil society and the public at large across every field. As a first step, they have collected the metadata and primary contents for over 300,000 datasets available on data.gov and will be releasing the data in the near future.
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Time TravelFind prior versions of web pages (called "Mementos" in this service) in many international web archives.
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ArchiveTeamWebsite intended to be an offloading point and information depot for a number of archiving projects, all related to saving websites or data that is in danger of being lost.
Comprehensive Government Information & Data
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Library of Congress Web ArchiveThe Library of Congress web archives are organized in thematic and event-based collections, and contain websites documenting a variety of U.S. and international organizations representing a broad range of subjects and topic areas. Examples include select U.S. government sites from the Legislative, Judicial, and Executive branch agencies; select foreign government sites; campaign websites and political parties documenting U.S. and select foreign elections; non-profit organizations; journalism and news; creative sites such as those documenting comics, music, authors, and art; legal sites; and international organizations.
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Federal Depository Library Program Web Archive"The FDLP Web Archive provides point in time captures of U.S. Federal agency websites, while preserving the functionality of the site to the extent possible. The aim is to provide permanent public access to Federal Agency Web content. GPO harvests and archives the websites with Archive-It."
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Congressional Web Harvest"As the repository of the official records of Congress, the Center for Legislative Archives conducts a web harvest of all congressional websites at the end of each Congress."
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DataLumosDataLumos is an ICPSR archive for valuable government data resources. You can find older versions of a lot of major data here, including a recent addition from the CDC.
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Census ReporterFree, open-source platform focused on making American Community Survey (ACS) data more accessible, including the recent upload of the 2022 1-Year ACS data.
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IPUMSIPUMS provides census and survey data from around the world integrated across time and space. IPUMS integration and documentation makes it easy to study change, conduct comparative research, merge information across data types, and analyze individuals within family and community contexts. Data and services available free of charge.
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End of Term CrawlThe End of Term Web Archive contains federal government websites (.gov, .mil, etc) in the Legislative, Executive, or Judicial branches of the government. Websites that were at risk of changing (i.e., whitehouse.gov) or disappearing altogether during government transitions were captured.
Note: Federal information/data may be replicated on state government websites. Try searching the relevant state organization's website (e.g., the Virginia Dept. of Health, the Colorado Dept. of Human Services).
Environmental Information & Data
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EDGI: Environmental Data & Government InitiativeThe Environmental Data & Governance Initiative (EDGI) is a research collaborative and network of diverse professionals promoting evidence-based policy-making and public interest science that advances the Environmental Right to Know (ERTK).
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Urban Ocean Lab Resource HubIncludes hundreds of resources—from datasets to case studies—to inform policymaking in coastal cities.
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Public Environmental Data ProjectThe Public Environmental Data Project is committed to preserving and providing public access to federal environmental data. Check their page for a list of the most recent data uploads.
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Silencing Science TrackerA joint initiative of the Sabin Center for Climate Change Law and the Climate Science Legal Defense Fund. This resource tracks government attempts to restrict or prohibit scientific research, education or discussion, or the publication or use of scientific information.
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Datasets in DataverseData uploaded by the Climate Change and Health Research Coordinating Center (CAFE).
Includes CDC's Social Vulnerability Index data. Most of the data included here focuses on health and the environment.
Healthcare Information & Data
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CDC datasets uploaded before Jan 28, 2025Datasets from the Centers for Disease Control for years prior to 2025, available via the Internet Archive.
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Datasets in DataverseData uploaded by the Climate Change and Health Research Coordinating Center (CAFE).
Includes CDC's Social Vulnerability Index data. Most of the data included here focuses on health and the environment.
Legal Information & Data
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Caselaw Access ProjectThe Caselaw Access Project (“CAP”) expands public access to U.S. law. The goal is to make all published U.S. court decisions freely available to the public online in a consistent format, digitized from the collection of the Harvard Law School Library.
Social/Demographic Information & Data
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Social Explorer This link opens in a new window
Social Explorer is an online research tool designed to provide quick and easy access to current and historical census data and demographic information. The easy-to-use web interface lets users create maps and reports to better illustrate, analyze and understand demography and social change.
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PolicyMapoffers a free tier that can be used to view basic information down to the tract-level
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Federal Reserve Economic Data (FRED)free and open source economic data resource, but includes some demographic data
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Justice MapOpen source income and race data visualization tool
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ESRI (American Community Survey data)GIS vendor that publishes several U.S. Census Bureau data sets, including the American Community Survey
Sources
Many resources and descriptions taken from Tufts University Libraries' Archived Data guide (Feb 5, 2025).