Postman used to be the default API client for every developer. Then, in late 2023, it killed the free team workspace tier, forcing any team with more than 3 collaborators onto the Team plan at $14/user/month. For a 10-person engineering team, that's $1,680 per year to send HTTP requests — software that, a few years earlier, had been free for unlimited use. The reaction from the developer community was swift, and a wave of open-source alternatives stepped in to fill the gap. Three of them have emerged as serious Postman replacements: Bruno, Insomnia, and HTTPie.
Bruno is the new challenger that's gotten the most attention. It's a fully open-source (MIT licensed) API client that stores your collections as plain text files in a folder you choose — meaning you can commit them to Git, diff them in pull requests, and collaborate via any version control system, with no cloud sync required. The team plan is genuinely free and unlimited; there's no per-user pricing at all. Bruno supports everything you'd expect: environments, variables, scripts, GraphQL, WebSocket, gRPC, and a clean tabbed interface. For teams that left Postman over the pricing change, Bruno is usually the easiest migration path because the UI is intentionally similar.
Insomnia is the older challenger, originally from Kong (now owned by Kong Inc.). It has a cleaner, more polished UI than Bruno and a stronger focus on design-first API workflows (OpenAPI editing, GraphQL schema design, mock servers). The free tier is generous for individuals but team features (shared workspaces, role-based access) require the Team plan at $5/user/month — much cheaper than Postman but not free. Insomnia is the right pick when you need a polished single-user experience or your team is small enough that the $5/user is worth the better UX. Kong also open-sourced the core client in 2023, so you can self-host the team sync server if you want to avoid the cloud entirely.
HTTPie is the developer-favorite terminal tool that recently got a desktop GUI. The terminal version is iconic — its syntax (`http POST api.example.com/users name=alice`) is so much more readable than curl that it's the default in many dev tutorials. The new desktop app is gorgeous, with a focus on the 'write a request, see the response beautifully formatted' workflow. It's free for individuals, with a paid Pro tier for cloud sync. HTTPie is the right pick if you primarily test APIs from the terminal, value beautiful output formatting, and don't need heavy collection management. It pairs well with Bruno or Insomnia — many developers use HTTPie for quick one-off requests and a heavier client for organized collections.
Beyond API clients, the broader 'Postman replacement' ecosystem includes a few tools worth knowing about. Hoppscotch is a web-based, fully open-source API client that runs entirely in your browser — no install required, collections sync via your GitHub or GitLab account, and it supports REST, GraphQL, WebSocket, SSE, and Socket.io. It's a great option for pair-programming sessions or quick tests from a machine where you can't install software. Thunder Client is a VS Code extension that puts a lightweight API client inside your editor — not as feature-rich as the standalone options, but extremely convenient if you live in VS Code. For automated API testing, k6 (open-source, Grafana Labs) is the modern alternative to Postman's collection runner.
The migration path away from Postman is more painful than it should be, because Postman's collection format is proprietary and changes between versions. Bruno and Insomnia both import Postman collections, but complex scripts, environments, and nested folders often need manual cleanup. The silver lining: once you've migrated to a Git-backed collection format (Bruno's default) or OpenAPI-spec-based workflows (Insomnia's strength), you'll wonder why you ever relied on a cloud-synced proprietary format in the first place. For most teams, the one-time migration cost pays for itself within the first month of not paying Postman's per-user fees.