Notice: Transition to Login.gov
We are enhancing the security of your account access by transitioning to
Login.gov, a secure and reliable federal login service.
Starting July 11th, you will no longer be able to log in to SEER*API using your previous local credentials. Your existing API keys will continue to function
as normal. You only need to log in with Login.gov if you need to manage your API keys (add, remove, or view).
What does this mean for you?
- If you already have a Login.gov account, simply use that account with the email address you used to create your account here.
- If you do not have a Login.gov account, you will be prompted to create one when you attempt to log in. Use the same email address as your existing account.
- This change will improve the security of your information and streamline access to other government services.
We understand this change may require a small adjustment, and we appreciate your cooperation. If you experience any difficulties, please
contact SEER API Technical Support.
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.
Recent Changes
July 11, 2025
- Transitioned to Login.gov for authentication
June 17, 2025
October 30, 2024
- Updated the recode endpoint to support additional site recode algorithms. In addition to SEER site recode, the API now also supports the International
Classification of Childhood Cancer and Adolescents and Young Adults (AYA) site recodes. See the /rest/recode for more information.
July 21, 2023
- Added initial support for NAACCR 24 to the NAACCR API
June 30, 2023
- Updates to MPH calculations
- Renamed all group IDs and names and exposed the names in the output objects.
- Implemented 2023 updates of solid tumor rules.
- Updated hematopoietic histology range.
March 2, 2023
- Added support for NAACCR 23 to the NAACCR API
