General Help for CDC WONDER


CDC WONDER: Information and Communication

Welcome to CDC WONDER -- Wide-ranging ONline Data for Epidemiologic Research -- an easy-to-use, menu-driven system that makes the information resources of the Centers for Disease Control and Prevention (CDC) available to public health professionals and the public at large. It provides access to a wide array of public health information.

CDC WONDER furthers CDC's mission of health promotion and disease prevention by speeding and simplifying access to public health information for state and local health departments, the Public Health Service, and the academic public health community. CDC WONDER is valuable in public health research, decision making, priority setting, program evaluation, and resource allocation.

CDC WONDER, developed by the Centers for Disease Control and Prevention (CDC), is an integrated information and communication system for public health. Its purposes are:

  1. To promote information-driven decision making by placing timely, useful facts in the hands of public health practitioners and researchers, and
  2. To provide the general public with access to specific and detailed information from CDC.

With CDC WONDER you can:

  • Access statistical research data published by CDC, as well as reference materials, reports and guidelines on health-related topics;
  • Query numeric data sets on CDC's computers, via "fill-in-the blank" web pages. Public-use data sets about mortality (deaths), cancer incidence, HIV and AIDS, tuberculosis, vaccinations, natality (births), census data and many other topics are available for query, and the requested data are readily summarized and analyzed, with dynamically calculated statistics, charts and maps.

The data is ready for use in desktop applications such as word processors, spreadsheet programs, or statistical and geographic analysis packages. File formats available include plain text (ASCII), web pages (HTML), and spreadsheet files (Tab Separated Values). All of these facilities are menu-driven, and require no special computer expertise.


CDC WONDER provides the following services:

  • Communication:  The web site provides a single point of access to a wide variety of reports and numeric public health data. The web site is recognized world-wide by the public health community, and widely used in the curriculum of many schools of public health.
  • Data release:  WONDER online databases provide data dissemination, online data query capabilities, analysis, visualization and reporting for public health data collections. CDC programs partner with CDC WONDER to provide external partners and the public with access to their data, in compliance with the CDC data release policy. WONDER's partners include programs throughout CDC and other agencies.
  • Data access:  The WONDER online databases provide data and analysis to support evidence-based assessment of public health programs and population health trends. CDC WONDER also includes the CDC Scientific Data archives, a collection of scientific datasets and documentation produced by CDC.
  • Software: 
    • WONDER web application:  WONDER system software is available for use by public health programs and agencies. This public domain software is intended for open platform operation. The end user is a "thin" client (HTML and internet connectivity). The web application is developed in Java, XSL and XML. The data server must support standard SQL queries, and may use either flat or relational tables. Legacy data values are permissible, because the design supports the translation of values via the metadata tables.
    • WONDER web service:  All WONDER online databases available via the WONDER web application software are accessible for automated web service data queries via the WONDER API for XML document exchange. This functionality supports the development of widgets or data mining. See WONDER API for more information.
  • Web hosting: CDC WONDER hosts web applications developed by other CDC agencies on the public-facing web site.
To learn more about our services, please contact us.


System Overview

CDC WONDER presents you with an array of health related data sets. Each data set can be queried using a series of menus.

Document collections, such as CDC Prevention Guidelines, are presented in a topic list or table of contents. In some cases, a full text search option is available as well.

Statistical databases are presented in a series of "fill in the blanks" request forms. You fill in the forms to specify the criteria for your data request, and then send the request to be processed. The results of your query are usually returned within seconds. If the system is delayed processing your request, however, some queries allow you to retrieve your results later, or you can have them e-mailed to you.

When you receive your results in CDC WONDER, you can view them online and then, if you desire, save them on your personal computer so that you can load them into another program. For example, you can generate charts or maps of your data, and paste these images into word processor documents or presentations. If you request numeric data, you may wish to load the data into a spreadsheet or statistical analysis program. You can do so by clicking the "Export" button to generate a tab separated file for download. Some software support the ability to paste rows copied from the table displayed in the web page.

Please refer to Data Sets and Documentation for more information.

System Requirements

The CDC WONDER home page is located on the world wide web at Specific pages and forms within WONDER are linked to from many other sites on the web.

Most of CDC WONDER will work with most web browsers. To fully use CDC WONDER, however, you need a browser with Java Script enabled. WONDER works with Internet Explorer version 6 and above, and with the Firefox version 1.5 and above.

Standard features:

These standard features are available for the WONDER online databases:
  • Standard look and feel for data query features:
    Select the "tab" shown near the top of the page for any WONDER online database to:
    • Request data with up to 5 cross-tabulations, such as national data grouped by state, county, age, race and sex. Find values within complex classification schemes, such as counties across several states.
    • The Results tab displays tables of summary statistics calculated in response to your data query. Tables are organized or nested by data groupings, such as counties nested under the "parent" state with state totals.
      • Click on the controls in the column headings to sort the rows or move the columns.
      • Use the Quick Options and More Options buttons above the table to make more changes, such as showing suppressed rows, row numbers, "high, medium and low" data distributions, or set custom break-points for data groups.
      • Click the Export button above the table to download the data as a tab-delimited text file.
      • Notes for context-sensitive caveats are below the results, along with the proper citation and a description of the query criteria.
    • Chart your data for enhanced visual analysis. You can choose from several styles of charts, select independent and dependent variables, combine measures, and more.
    • Map each data element, select quantiles or set custom break-points for data distributions, display interstates, rivers and labels, choose your color scheme, and more. CDC WONDER and GATHER have collaborated to produce maps for WONDER data query applications. GATHER is an acronym for Geographic Analysis Tool for Health & Environmental Research (GATHER), a product of the Geographic Research, Analysis and Services Program (GRASP), at the National Center of Environmental Health (NCEH) / Agency for Toxic Substances and Disease Registry (ATSDR) at CDC.
    • Save your request or results data for later use. The current state of a Request, Results table, Chart, or Map can now be saved by clicking the "Save" button. The saved pages are accessed via a unique URL created by the system which you can save and reuse.
    • The About tab provides a quick reference to the data description and data source.
  • Logon requirement removed.
    We retired all WONDER user accounts in August 2003, in order to make this public system more easily accessible to all researchers in public health and population health science.
  • Home pages:
    We have identified the list of WONDER system data queries on our home page. The inclusive list of additional CDC web resources is still available, click on the Topics tab for a categorized list, or click on the A-Z Index tab for an alphabetical list.
  • Search:
    Search the WONDER databases, or search the Scientific Data and Prevention Guidelines document collections.
  • Data Access Web Service
    Access data in the WONDER online databases immediately with automated data queries in XML format over HTTP, for use in your own web pages or widgets. See WONDER API or Contact us to learn more.

Data Sets and Documentation

CDC WONDER is a powerful tool for retrieving and analyzing public health data. Before using any data set, we urge you to review the detailed data set documentation to ensure that you have a thorough understanding of the nature and limitations of the data sets. If you have any questions regarding a CDC WONDER data set, please contact CDC WONDER Customer Support.

Brief summaries of the content of all CDC WONDER data sets are available here and from the CDC WONDER home page.

Comprehensive documentation for a given data set is available in the online help under each data set's request screen.

Querying Data Sets

CDC WONDER presents you with an array of health related data sets. Each data set is queried using a series of menus. The array of data sets available through CDC WONDER changes over time as CDC works to make new data sources available and as problems are encountered and resolved.

Document collections, such as CDC Prevention Guidelines, are presented in a topic list or table of contents. In some cases, a full text search option is available as well. These documents are pre-formatted and organized on the WONDER web site so that you can access them instantly.

Statistical databases are presented in a series of "fill in the blanks" request forms. You fill in the forms to specify the criteria for your data request, and then send the request to be processed. Behind the scenes, your request is forwarded the appropriate database server on the CDC network.

Each data request form provides an entry allowing you to label or describe the query. This description appears on the results page that is returned, and is also used as the default filename, should you "export" your data results to a tab-delimited file for download.

Exporting Data

When you receive your results in CDC WONDER, you can view them online and then, if you desire, save them on your personal computer so that you can load them into another program.

If you retrieved a text document, for example, you may wish to load it into a word processor. You can do so by using the "File" and "Save As" buttons on your browser to save it as an ASCII text or html file, and then loading the file into your word processor.

If you requested numeric data, you may wish to load the data into a spreadsheet or statistical analysis program. The online databases show the "Export" button above the data results. Click on this button to download a tab delimited file. Refer to Data Export Help for more information about importing the data into other applications.

Contacting CDC WONDER User Support

For support and technical assistance with CDC WONDER, or to share your ideas and opinions, click here to contact our customer support team. Links to contact us appear at the top and bottom of most WONDER pages. When reporting a problem, be as specific as possible, and try to describe the steps you took prior to encountering the error. Also, note any error messages you received from CDC WONDER or from your Web browser. It may be necessary for the support representative to attempt to recreate the error so be as detailed as possible.


The computer programs that make up CDC WONDER were created by the Centers for Disease Control and Prevention. The Centers for Disease Control and Prevention is an agency of the U.S. Department of Health and Human Services. All data are provided by CDC offices or other agencies.


We are very grateful to our "founding fathers," Andrew Friede, MD, MPH, Patrick O'Carroll, MD, MPH, Howard W. Ory, MD, MSc, and Joseph Reid, PhD for providing the system's original guiding vision and for their continuing mentorship. Special thanks to Jerry G. Gentry and William A. Norman for collaborating on mainframe database and communications systems, and Mike Cox and Kenneth McKneely for collaborating on Wide Area Network communications systems.

We are indebted to our colleagues in every part of CDC who made data available to us, and who collaborated in screen and report designs for their data sets. Grateful acknowledgment is given for the contribution of our earliest users, largely Epidemic Intelligence Service Officers, who have made hundreds of thoughtful suggestions that have been incorporated into the system. Dan Peterson and Richard Sun contributed greatly to our early development. We would especially like to thank our colleagues at the Information Network for Public Health Officials (INPHO) project: David A. Ross and Edward Baker Jr. for their collegiality.

Current Team Members
Darrell Bauer Yvette Dominique Sigrid Economou
Ugo Okeke   Shayla Williamson

Past Contributors and Team Members
(gone but not forgotten...)
Jo Altman Vincent T. Alvarez Rick Anderson
Marrietta Barral George Blanchard Barbara Boyett
Patricia Brindley Fernando Brown Anne Cauley
Robb Chapman Alex Charleston Linda Cleveland
John Cottrell Tim Coutu Jennifer Davis
Anna DeStefano Shannon Dewitt Boris Donald
Earnestine Dooley Greg Digsby Connie Dorner
John Dyer Steve Einbender Robert Evans
Robert Fagan Bob Flesch Howard Frazier
Angela Freeman Ricky Freyre Raymond Frigola
Cheri Gatland-Lightner Jodi Glacer Juedienne Gordon
Ray Green Fred Guthrie Miranda Hall
Jimmy Hammond Ryan Haygood Brett Headley
Heitzso Jeffrey R. Hermann Harry Holden
Natalie Huet, MPH Dee Hughes Nancy Hughes
Gidado-Yisa Immanuel Scott Janes Angela Jarrad
Tracie M. Jones Troy Jordan Craig Kassinger
Susan Kerht Joan Kennedy Carol Knowles
Bryan Korff Lew Levy Kenneth S. Lightner
Tracy Lin Kenneth Long Matt Lupo
John Macke Lee Maddox Michael Micco
Mike Molinari Myra Montalbano Fran Moore
Lee Nadelman Evelyn Olagundoye Truls Ostbye
Bill Parks Veer Pawate Lesley Peters
Ron Peterson Mark Puckett Sujitra Priest
Michele Renshaw Barry Rhodes Daniel Rosen
Jerry T. Sanders Lois Starr Robert Thralls
Bryant Upton Ed Weber Susan M. Wilkin
Johann Michael Wood Dianne Wylie  

This page last reviewed: Friday, June 17, 2022
This information is provided as technical reference material. Please contact us at