Compare Postman alternatives
| Tool | Stars | Forks | License | Self-hosted |
|---|---|---|---|---|
 Hoppscotch | 79.4K | 5.9K | MIT | Yes |
 Bruno | 44.6K | 2.5K | MIT | Yes |
 Voiden API Client | 1.1K | 42 | Apache 2.0 | Yes |
Postman is the most widely used API client, but it's a proprietary, increasingly cloud-first product — collections sync to Postman's servers by default, and advanced collaboration features sit behind paid plans.
All three open-source alternatives below remove the account requirement and the cloud lock-in; they differ in how far they rethink the workflow.
The best open-source alternatives to Postman
1. Hoppscotch — best drop-in replacement
Hoppscotch is the closest to Postman's day-to-day workflow: compose and send REST, GraphQL, and WebSocket requests in a fast, clean interface, organize them into collections, and switch environments — everything a Postman user expects, without an account.
It runs in the browser with zero install, and MIT licensing means teams can self-host the whole thing behind their own firewall. Team collaboration features are thinner than Postman's paid tiers, which matters mostly for large organizations.
Why pick it over Postman:
- No account required, no forced cloud sync
- REST, GraphQL, WebSocket, and more in one interface
- Runs in the browser instantly or self-hosts via Docker
- MIT-licensed with a very active community (79k+ GitHub stars)
- The gentlest migration for a team used to Postman
2. Bruno — best for Git-based teams
Bruno rejects the cloud-workspace model entirely: collections are plain-text files (in its Bru markup) that live in your repository, get reviewed in pull requests, and travel with your code. There is no sync to opt out of, because there's no cloud at all.
Created by a solo developer frustrated with Postman's direction and now backed by a large community, it's the strongest pick when collection ownership and versioning are the reason you're leaving.
Why pick it over Postman:
- Collections as plain text files — diff, review, and merge them like code
- Fully offline; API keys and payloads never leave your machine
- Native desktop app, MIT-licensed
- Version control built into the workflow, not bolted on
- No account, no telemetry-driven upsell
3. Voiden API Client — best for docs-as-code workflows
Voiden goes a step further than Bruno: runnable API requests and their documentation live together in Markdown-based .void files, with reusable blocks for headers, auth, and environments. Design, test, and document an API in one Git-native place.
It's the newest of the three — Apache-2.0 licensed, offline by default, with a plugin SDK — so expect a smaller ecosystem and a fast-moving product.
Why pick it over Postman:
- Requests and API docs in the same Markdown files, committed to Git
- Composable request blocks instead of copy-pasted headers
- Offline-first: no account, no telemetry, no cloud dependency
- Apache-2.0 licensed desktop app for macOS, Windows, and Linux
FAQ
Is there a free, open-source alternative to Postman?
Yes. Hoppscotch, Bruno, and Voiden API Client are all open source and free to self-host or run locally.
What's the best open-source alternative to Postman?
Hoppscotch is closest to Postman's general workflow. Bruno is the better pick if Git-based collaboration on API collections is the priority.
Can I keep my API collections in Git instead of the cloud with a Postman alternative?
Yes. Bruno and Voiden API Client both store collections as local files designed to be committed to Git, unlike Postman's cloud-synced collections.
What are the top open-source alternatives to Postman?
Browse all open-source alternatives to Postman above, or explore the full Developer Tools category for more options.