1. Postman is the most efficient way to test, develop and document APIs.

    freemium $8.0 / Monthly (Per user/month billed annually)

  2. Gravitee.io is a flexible, lightweight and an open source API management solution.

    freemium

  3. Collaborative design, instant API mock, generated documentation, integrated code samples, debugging and automated testing

  4. Intelligent and complete API platform

  5. Create, publish, maintain, monitor, and secure APIs at any scale

  6. Django REST framework is a toolkit for building web APIs.

  7. Tyk is an open-source API gateway and API management platform.

  8. Paw is a REST client for Mac.

  9. API Integration Solution for Developers: 10x Faster • Less Maintenance • No Vendor-Lock-In. Use the same clean interface across multiple providers.

  10. WSO2 API Manager is a 100% open source enterprise-class solution that supports API publishing, lifecycle management, application development, access control, rate limiting and analytics in one cleanly integrated system.

  11. API management

  12. Akana provides a comprehensive suite of API management/security applications.