The SEER API is a RESTful Web service that supports various SEER Program data sets and mapping. This service is available to developers who wish to incorporate SEER resources into their own systems. These resources include databases and tools developed to enhance registry operations and quality improvement. The SEER API is designed for integration into registry computer systems and is not designed to be accessed by end-users.

The goal of SEER API is to provide a centralized repository of SEER Program tools that is available to all programming environments and operating systems. The API is based on REST principles, therefore, it is very easy to write and test applications. You can use your browser to access URLs and to test APIs. Any programming language that can read HTTP data from a URL can use web services. Results are returned in JSON format which can be easily parsed and interpreted. See the Usage page for language-specific examples.

The SEER API powers a variety of SEER tools, including:

The Surveillance, Epidemiology and End Results (SEER) Program is a premier source for cancer statistics in the United States. The SEER Program collects information on incidence, prevalence and survival from specific geographic areas representing 28 percent of the US population and reports on all these data plus cancer mortality data for the entire country.


November 5th, 2014

The Disease (/rest/disease/:version) and Glossary (/rest/glossary/:version) search APIs were modified. If you use the search API you will most likely need to make changes to your code.

  • The number of results returned in a single call is now limited by the "count" parameter. If "count" is not specified, 25 results will be returned. Up to 100 results can be returned in a single API call.
  • An "offset" parameter was added. This allows results to be "paged" and returned in chunks.
  • The "count-only" parameter was removed. This is no longer needed since all search results now include a "total" field which represents the total number of results regardless of "count" and "offset".

September 29th, 2014

The SEER*Rx APIs (/rest/rx) were modified to match the structure of the disease and glossary APIs. The Rx data is now going to be updated regularly.

A new set of APIs (/rest/surgery) were added to give access to SEER Site-Specific Surgery Codes. The current data comes from Appendix C on the SEER web site.

The Usage page was updated to include a simple using the seerapi-client-java library.

March 10th, 2014

A Changelog section was added to document all API changes.

January 17th, 2014

The Hematopoietic and Lymphoid Neoplasm API was replaced with the Disease API. The new API contains the same types of diseases as before but will also include Solid Tumors as well. The following changes are now in place:

  • The Hematopoietic & Lymphoid Neoplasm API (/rest/hemato) has been removed.
  • A new Disease API was added (/rest/disease). This API replaces the previous Hematopoietic API. It allows the user to retrieve data for both Hematopoietic and Solid Tumors, however, please note that the while the Hematopoietic data is currently production-ready, the Solid Tumor data is provided only as a preview. Solid Tumor data editing is still ongoing and this data should not be thought of as complete. A notification will be sent out when the Solid Tumor data is ready for production use.
  • The Hematopoietic data is now updated regularly in order to correct mistakes. Major releases will be announced via the SEER website.
It is important to remember when searching for disease data (rest/disease/:version) that the API call can return both Hematopoietic and Solid Tumor data. The Solid Tumor data, however, is being provided as a preview only. In order to retrieve data that is ready for use in your systems, please make sure to include the HEMATO parameter when retrieving disease data. If you do not provide a parameter, you will be retrieving data for both Hematopoietic and Solid Tumors.

Full documentation for the new API can be found on the API documentation page.