CNPJAPI

API Documentation

CNPJAPI is a Brazilian REST API for company registration data lookup by CNPJ, based on public data from Receita Federal (Brazil's tax authority). Responses are in JSON and cover identification, registration status, economic activities (CNAE), address, contact and shareholder structure (QSA). It is used to integrate CNPJ lookup into systems, ERPs, CRMs and registration/onboarding flows.

  • Base URL: https://api.cnpjapi.com.br
  • Authentication: API key in the Authorization: Bearer header (see Authentication)
  • Format: JSON, fields in PascalCase

In this documentation

  • Look up a CNPJ - the GET /{cnpj} endpoint, a request example, the JSON response and the dictionary of returned fields.
  • ReceitaWS-compatible - migrate by swapping only the host: same response via GET /v1/cnpj/{cnpj} or ?formato=receitaws.
  • Authentication - how to generate and use the API key, and the difference between the open web lookup and programmatic use.
  • Limits and plans - requests per minute, monthly quota and the behavior on 429 Too Many Requests.
  • Check your quota - the GET /cota endpoint to track this month's usage without spending quota.
  • Errors - the API's HTTP status codes and what each one means.

Get started

Create your free account at https://app.cnpjapi.com.br, generate your API key and make your first request in minutes. There is a free plan to get started; limits vary by plan.