Alternatives to Postman

Insomnia

Direct competitor

Desktop and CLI API client for designing, debugging, and testing REST, GraphQL, WebSocket, SSE, and gRPC APIs, built and maintained by Kong.

Both are widely used desktop API clients for designing, debugging, and testing REST/GraphQL APIs, and Kong publishes direct migration guides and comparison pages against Postman.

Relationship verified September 25, 2026.

Hoppscotch

Direct competitor

Open-source, lightweight API development ecosystem for building and testing REST, GraphQL, WebSocket, SSE, and MQTT requests, available as a web app, self-hosted instance, and desktop/CLI tools.

Hoppscotch is commonly positioned and documented (including by Postman itself) as an open-source alternative API client to Postman, with dedicated migration paths between the two.

Relationship verified September 25, 2026.

Stoplight

Direct competitor

API design, documentation, and mocking platform built around the OpenAPI Specification; acquired by SmartBear in 2023 and now integrated into SmartBear's Swagger/API Hub portfolio.

Postman publishes a direct comparison page contrasting Stoplight's API design focus with Postman's full API lifecycle platform, indicating overlapping use cases.

Relationship verified September 25, 2026.

SwaggerHub

Direct competitor

Collaborative platform for designing, documenting, and governing APIs using the OpenAPI Specification; owned by SmartBear and now marketed as part of the Swagger/API Hub product line (also referred to as Swagger Studio).

Both platforms are used for API design and documentation with OpenAPI, and third-party and vendor comparisons commonly evaluate them as alternatives for API design workflows.

Relationship verified September 25, 2026.