Developer tools

Postman alternatives

2 open-source projects that already do this job. Free to use - not free to run, which is what the numbers on the right are for.

The full assessment →

The projects

Kong/insomnia39,935Apache-2.0Cross-platform GUI API client for REST, GraphQL, WebSockets, SSE, and gRPC with cloud and local storage.Open on GitHub hoppscotch/hoppscotch79,989MITOpen-source API development suite with web, desktop, and CLI clients plus request collections and runners.Open on GitHub

What you give up either way

Advanced team collaboration, RBAC, and enterprise governance features
Integrated monitoring, private runners, and large-scale API catalog capabilities
Extensive built-in integrations and marketplace connectors
Postman AI features and pooled AI credits
Brand trust, support SLAs, and audit/compliance tooling

An open-source project doing the core job proves a replacement is possible. It does not prove it matches Postman, and it does not prove anyone has run it for a month. How we decide.