ExchangeRate-API Open Access API

openapi: 3.1.0
info:
  title: ExchangeRate Enriched Data Open Access API
  description: ExchangeRate-API is a currency exchange rate API providing authoritative daily and intraday foreign exchange rates for 161 currencies. The v6 API surface includes Standard (Latest) rates, Pair conversion, Enriched data (locale, symbol, flag), Historical rates back to 1990, Supported codes, and an API request Quota endpoint. A separate no-key Open Access endpoint (open.er-api.com) provides once-daily rates with attribution.
  version: 6.0.0
  termsOfService: https://www.exchangerate-api.com/terms
  contact:
    name: ExchangeRate-API Support
    url: https://www.exchangerate-api.com/contact
    email: contact@exchangerate-api.com
  license:
    name: Proprietary
    url: https://www.exchangerate-api.com/terms
servers:
- url: https://v6.exchangerate-api.com/v6
  description: ExchangeRate-API v6 Production (API key required)
- url: https://open.er-api.com/v6
  description: ExchangeRate-API Open Access (no API key, attribution required)
security:
- apiKeyPath: []
tags:
- name: Open Access
  description: Free no-key endpoint with once-daily rates and attribution requirement.
paths:
  /latest/{base_code}:
    get:
      tags:
      - Open Access
      summary: Get Open Access Latest Rates
      description: Returns the latest exchange rates from a base currency via the no-API-key Open Access endpoint (https://open.er-api.com/v6). Requires attribution back to exchangerate-api.com. Updates once daily and is rate limited.
      operationId: getOpenAccessLatest
      servers:
      - url: https://open.er-api.com/v6
      parameters:
      - $ref: '#/components/parameters/BaseCode'
      responses:
        '200':
          description: Successful response with conversion rates.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/OpenAccessResponse'
        '429':
          description: Rate limit exceeded; retry after 20 minutes.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
components:
  parameters:
    BaseCode:
      name: base_code
      in: path
      required: true
      description: ISO 4217 three-letter currency code for the base currency (e.g. USD).
      schema:
        type: string
        pattern: ^[A-Z]{3}$
        example: USD
  schemas:
    OpenAccessResponse:
      type: object
      description: Open Access (no-key) response.
      properties:
        result:
          type: string
          description: Status indicator.
        provider:
          type: string
          format: uri
          description: Provider attribution URL (exchangerate-api.com).
        documentation:
          type: string
          format: uri
          description: Link to the documentation.
        terms_of_use:
          type: string
          format: uri
          description: Link to the terms of use.
        time_last_update_unix:
          type: integer
          description: Last update Unix timestamp.
        time_last_update_utc:
          type: string
          description: Last update in UTC.
        time_next_update_unix:
          type: integer
          description: Next update Unix timestamp.
        time_next_update_utc:
          type: string
          description: Next update in UTC.
        time_eol_unix:
          type: integer
          description: End of life Unix timestamp for the response data (if applicable).
        base_code:
          type: string
          description: The base currency requested.
        rates:
          type: object
          description: Object mapping ISO 4217 currency codes to exchange rates from the base currency.
          additionalProperties:
            type: number
    ErrorResponse:
      type: object
      description: Standard error envelope returned when a request cannot be fulfilled.
      properties:
        result:
          type: string
          description: Status indicator (error).
          example: error
        error-type:
          type: string
          description: Machine-readable error code.
          enum:
          - unsupported-code
          - malformed-request
          - invalid-key
          - inactive-account
          - quota-reached
          - plan-upgrade-required
          - no-data-available
  securitySchemes:
    apiKeyPath:
      type: apiKey
      in: path
      name: api_key
      description: ExchangeRate-API uses an API key embedded in the URL path (after /v6/).