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

April 8, 2022

  • The site-specific surgery API was updated to include additional support the 2022 diagnosis year.

June 3, 2021

  • The structure of the staging schema metadata changed from a list of strings to a list of objects.

    The old structure looked like

    "metadata": [ "ITEM1", "ITEM2" ]
    The new structure looks like
    "metadata": [ { "name": "ITEM1" }, { "name": "ITEM2" } ]
    In future staging algorithm versions, the metadata will also support "start" and "end" years for individual metadata items. Note that if "start" is not present, the item is considered valid since the first year the algorithm version was valid. Similarly if "end" is not present, the item is considered valid as long as the algorithm version is valid.
    "metadata": [ { "name": "ITEM1", "start": 2020 }, { "name": "ITEM2", "start": 2018, "end": 2021 } ]