Developers and Researchers

The OpenOMB project aims to make the Office of Management and Budget's apportionments data more accessible to many different audiences. We know that direct access to our data can be much easier to work with than using the website for certain purposes. If you would like to see different methods or endpoints to the data, please contact us.

If you would like direct access to the source data, it is available at apportionment-public.max.gov.

Data collection last completed on Nov 1, 2025.

API

We provide a basic API for developers to utilize the data in our applications.

It is important to note that we try to avoid altering the original data, but we do some basic cleanup and re-structuring of the data for better usability and functionality. For more details about how our application works and how our data is processed, please see our codebase on Github and specifically our database schema files.

General responses

Responses from the API will be in JSON format. A successful response will include the following.

{
  query: {
    ...any query parameters that were provided
  },
  paging: {
    // If available
    page: 1, // The page number requested
    offset: 0, // The offset of the results
    pages: 10, // Total number of pages available
    size: 50, // Number of results per page
    count: 100 // Total number of results available
  },
  results: ...data
}

Endpoints

Endpoint	Description	Query parameters
`/api/v1/files/recent`	Get recently approved files.	`limit` - Limit number of results; defaults to 50; limit is 1000.
`/api/v1/files/[fileId]`	Get the details of a single file if you know the File ID	`sourceData` - Set to anything to include source data in response; defaults to false.
`/api/v1/files/search`	Search for files using various parameters. Can copy the URL query parameters from the search page.	`term` - Keyword to search in multiple fields across files, lines, and footnotes. `agencyBureau` - Search in a specific agency or bureau, in format ACCOUNT_ID or ACCOUNT_ID,BUREAU_ID. `tafs` - Keyword search specifically for TAFS. `account` - Keyword search specifically for accounts. `approver` - Approver ID; utilize multiple approver query params for multiple values. `year` - Approval year; utilize multiple year query params for multiple values. `approvedStart` - Date in ISO YYYY-MM-DD format to limit approvals by. `approvedEnd` - Date in ISO YYYY-MM-DD format to limit approvals by. `apportionmentType` - Limit files based on source type. Should be either "Letter (PDF)" or "Standard (Excel)". `lineNum` - Line number ID; utilize multiple year query params for multiple values. `footnoteNum` - Contains a certain footnote type, either A or B. `sort` - Should be approved_desc, approved_asc, agency_asc, bureau_asc, or account_asc. Defaults to approved_desc. `limit` - Limit number of results; defaults to 50; limit is 1000. `page` - Page number to return; defaults to 1.
`/api/v1/folders`	Get the full list of folders.
`/api/v1/collections`	Get a list of completed collections (i.e. scraping runs).