Best Open Source Alternatives to Postman in 2026

Postman Just Made Teams Pay — and Your API Data Is Still in Their Cloud

In March 2026, Postman restructured its pricing. The Free plan is now solo-only. If you want to collaborate with even one other developer, you need the Team plan at $19/user/month. The Solo plan runs $9/month for individual use with more features than the free tier, and Enterprise pricing climbs from there.

Here is what Postman costs in 2026:

Plan	Price (per user/month)	Notes
Free	$0	Solo use only, 50 AI credits, limited collections
Solo	$9	Single user, more storage and integrations
Team	$19	Collaboration features, shared workspaces
Enterprise	Custom	SSO, SCIM, audit logs, RBAC

For a 10-person backend team on the Team plan, that is $2,280/year. For 25 developers, $5,700/year — just to send HTTP requests and share collections.

But pricing is only half the problem. Postman stores your API collections, environments, and request history on their cloud servers by default. Every endpoint, every header, every auth token you test passes through Postman's infrastructure. For teams working with internal APIs, healthcare data, or anything subject to compliance requirements, this is a real concern.

Developers want tools that respect two things: their wallets and their data. Here are the six best open source and privacy-focused alternatives to Postman in 2026.

TL;DR

Bruno is the best overall Postman replacement — it stores collections as plain-text files on your filesystem, works entirely offline, costs nothing, and fits naturally into Git workflows. For teams that want a web-based collaborative experience closer to Postman's UI, Hoppscotch is the strongest choice with real-time collaboration and self-hosting support. If you already live in VS Code, Thunder Client keeps everything in your editor, though its free tier has been cut back significantly.

Key Takeaways

• Bruno (30K+ GitHub stars) stores API collections as .bru files on your filesystem. Zero cloud sync, zero cost, fully Git-native. The strongest privacy story of any tool here.
• Hoppscotch (68K+ GitHub stars) is the most popular open source API client by star count. Web-based with desktop and CLI options, MIT-licensed, supports REST, GraphQL, WebSocket, MQTT, and SSE.
• Insomnia (35K+ GitHub stars) is backed by Kong with Apache-2.0 licensing. Offers local Scratch Pad, Local Vault, and optional cloud sync. Insomnia 12 introduced MCP server testing support.
• HTTPie has an open source CLI (BSD-3-Clause) loved for its human-readable syntax. The Desktop app is closed source with paid pricing — a mixed bag for open source purists.
• Thunder Client offers a lightweight VS Code extension experience but moved collections behind a paywall in August 2025. Free tier is now limited to individual requests without collections.
• Kreya is the best option for teams working heavily with gRPC. Free tier available, local-first data storage, and native support for gRPC, REST, GraphQL, and WebSocket protocols.
• Postman's free tier is now solo-only. If your team relied on free Postman workspaces, you are already paying or looking for alternatives.

Quick Comparison

Feature	Bruno	Hoppscotch	Insomnia	HTTPie CLI	Thunder Client	Kreya
Offline Support	Full	Desktop app	Scratch Pad	Full (CLI)	Full	Full
Collection Storage	Filesystem (.bru)	Cloud or self-hosted	Local / Cloud / Git	Local	VS Code storage	Local (JSON)
Environment Variables	Yes	Yes	Yes	Sessions	Yes	Yes
Scripting	JavaScript	Pre/Post scripts	Pre-request + tests	CLI scripting	GUI-based testing	Kreya Script (JS)
Team Collaboration	Git-based	Real-time (cloud/self-host)	Cloud sync or Git	Shared sessions	Git-based export	Git-based
Git-Friendly	Native (.bru files)	Export/import	Git sync option	N/A	JSON export	JSON project files
gRPC Support	Yes (v3+)	No	Yes	No	No	Native
GraphQL Support	Yes	Yes	Yes	No	Yes	Beta
License	MIT	MIT	Apache-2.0	BSD-3-Clause (CLI)	Proprietary	Proprietary (free tier)
Price	Free	Free (self-host)	Free (local)	Free (CLI)	Free (limited)	Free (limited)

Bruno — Best Overall Postman Replacement

Bruno takes a fundamentally different approach to API collections: they are files on your computer. Not blobs in a database. Not JSON synced to someone else's cloud. Plain-text .bru files stored in a folder on your filesystem, right next to your source code.

What It Does Well

The Bru markup language is human-readable and diff-friendly. Each request becomes a .bru file that you can commit, review in pull requests, and merge with standard Git tools. This makes Bruno the most naturally version-controlled API client available. No plugins, no export steps, no sync conflicts — your API collections are just part of your repo.

Bruno supports REST, GraphQL, gRPC (added in v3), and WebSocket protocols. Environment variables work through .env files on your filesystem, which means your secrets stay on your machine and in your .gitignore. Pre-request and post-request JavaScript scripting handles auth token flows, response validation, and variable chaining. The Postman script translator helps migrate existing test scripts.

Recent updates in 2025 added OAuth2 support, Azure Key Vault and AWS Secrets Manager integrations, OpenAPI import, and array/object variable interpolation. Version 3.1.4 (February 2026) is the latest release.

Privacy and Data Storage

Bruno's privacy model is the simplest on this list: there is no cloud. Your data lives on your filesystem. Period. There is no account to create, no telemetry to opt out of, no terms of service granting access to your API collections. For regulated industries, this is the easiest compliance conversation you will ever have.

Limitations

Bruno v3 introduced breaking changes, so teams upgrading from v2 need to plan for migration. The UI is functional but not as polished as Postman or Hoppscotch — it prioritizes utility over visual design. Real-time collaboration does not exist because there is no server component; teams collaborate through Git instead, which requires everyone to be comfortable with Git workflows. There is no web-based version.

Best For

Solo developers and teams that already use Git-based workflows. If you want your API collections versioned alongside your code with zero cloud dependencies, Bruno is the clear winner.

Hoppscotch — Best Web-Based Collaborative Alternative

Hoppscotch (formerly Postwoman) is the most starred open source API client on GitHub, and for good reason. It delivers a clean, fast web interface that feels closer to Postman's UX than any other open source option while remaining fully MIT-licensed.

What It Does Well

The web-based interface loads instantly and supports REST, GraphQL, WebSocket, MQTT, SSE, and Socket.IO — the broadest protocol coverage on this list. Real-time collaboration lets multiple team members work on the same project simultaneously, which is something Bruno and most other alternatives cannot offer without Git.

Environment variables, pre-request scripts, and post-request tests are all supported. Code snippet generation exports requests to popular languages and frameworks. The desktop app provides offline access, and the CLI enables CI/CD integration.

Self-hosting with Hoppscotch Enterprise gives you the full collaboration experience on your own infrastructure. The Community Edition is self-hostable via Docker with admin features, user management, and team workspaces.

Privacy and Data Storage

Self-hosted Hoppscotch keeps all data on your infrastructure. The cloud version at hoppscotch.io stores data on Hoppscotch's servers, but since the project is fully open source and self-hostable, you have the option to avoid third-party data storage entirely. The desktop app can work offline without any cloud connection.

Limitations

Self-hosting requires running a full web application stack (Node.js backend, database, the works). The web-only nature of early Hoppscotch was a drawback, but the desktop app addresses this. Import/export from Postman works but may not preserve every scripting detail. The MQTT and Socket.IO support, while unique, can feel like early-stage features compared to the polished REST and GraphQL experience.

Best For

Teams that want a Postman-like collaborative experience without Postman's pricing. Especially strong for organizations that can self-host and want real-time collaboration with full data sovereignty.

Insomnia — Most Flexible Storage Options

Insomnia, maintained by Kong under the Apache-2.0 license, has had a rocky few years with controversial changes around mandatory accounts and cloud sync. But Kong course-corrected, and Insomnia in 2026 offers the most flexible storage architecture of any API client.

What It Does Well

Insomnia gives you three storage modes: Scratch Pad (fully local, no account needed), Local Vault (local storage with account features), and Cloud Sync (full collaboration with cloud backup). You can switch between these modes per project, which means your sensitive internal API collections can stay in Local Vault while your team's shared public API tests use Cloud Sync.

Protocol support covers REST, GraphQL, gRPC, WebSocket, and SSE. Insomnia 12 introduced native MCP (Model Context Protocol) client support for testing and debugging MCP servers — a forward-looking feature as AI tool integrations become more common.

The plugin ecosystem is mature, with community plugins for authentication providers, code generators, and custom themes. Pre-request scripting and test assertions use a familiar JavaScript-based syntax.

Privacy and Data Storage

Scratch Pad mode stores everything locally with zero network requests. No account required. This is Insomnia's answer to the backlash from the 8.0 release that originally required cloud accounts. Local Vault adds account-level features while keeping data on your machine. Cloud Sync is opt-in and per-project, so you have granular control over what leaves your device.

Limitations

Insomnia's history of controversial product decisions has eroded trust with parts of the developer community. The 8.0 mandatory account requirement (later reversed), followed by the open source license changes, left some developers wary. While the current state is strong, you are depending on Kong's continued commitment to the open source model. The UI can feel heavier than Bruno or Hoppscotch, and the application is Electron-based, which means higher memory usage.

Best For

Teams that want enterprise-grade features with flexible data sovereignty. The per-project storage model is ideal for organizations that need cloud collaboration for some workflows and strict local-only storage for others.

HTTPie — Best CLI Experience (Desktop Is Not Open Source)

HTTPie needs to be discussed in two parts. The CLI is open source (BSD-3-Clause), beloved, and free. The Desktop app is closed source and paid. These are fundamentally different products sharing a brand.

What It Does Well

The HTTPie CLI is arguably the best command-line HTTP client ever built. Its syntax is designed for humans — http GET api.example.com/users is more readable than the equivalent curl command. JSON request bodies, authentication, sessions, file uploads, and output formatting all use intuitive syntax. Sessions persist authentication and headers across requests, functioning as lightweight environments. The output is syntax-highlighted by default — no piping through jq required.

The CLI stores session data locally. No cloud, no accounts, no telemetry.

Limitations

The Desktop app is not open source. The CLI does not have collections, visual environment management, or point-and-click request building — it is a pure terminal tool.

Best For

Developers who prefer the terminal and want a more ergonomic experience than curl. Just do not confuse the open source CLI with the proprietary Desktop app.

Thunder Client — Best for VS Code Users (With Caveats)

Thunder Client is a lightweight API testing extension that runs inside VS Code. No context switching, no separate application, no extra memory overhead from another Electron app.

What It Does Well

The integration with VS Code is seamless. Requests open in editor tabs alongside your code. Environment variables support local, global, and active scopes. Scriptless testing uses a GUI-based approach where you define assertions through dropdowns rather than writing JavaScript. All data is stored locally in your VS Code workspace with no cloud component.

Limitations

Thunder Client moved collections behind a paywall in August 2025. The free tier no longer supports collections — organizing requests requires a paid plan (Starter at $3/month with 30 collection runs, Business at $7/month with 250 runs, Enterprise at $16/user/month for unlimited). Thunder Client is also not open source — it is a proprietary extension with a free tier. The source code is not available, and it is locked to VS Code (with JetBrains support incoming).

Best For

Individual developers in VS Code who need quick API testing without leaving their editor. Teams needing collections should evaluate the paid plans against fully free alternatives like Bruno.

Kreya — Best for gRPC-Heavy Workflows

Kreya occupies a niche that none of the other tools on this list fill as well: native gRPC support as a first-class citizen, not an afterthought.

What It Does Well

gRPC support in Kreya is genuinely native. It reads .proto files directly, generates the UI from your service definitions, and handles all streaming RPC types (unary, server streaming, client streaming, and bidirectional) cleanly. REST, WebSocket, and SSE are also supported, with GraphQL in beta. The 2025 updates added Kreya Script (JavaScript-based scripting), JWT authentication, cURL/gRPC command export, and snapshot testing.

All data is stored locally on your device in JSON project files designed for Git sharing. No cloud sync, no accounts required for the free tier.

Limitations

Kreya is not open source. The source code is on GitHub, but the license is proprietary. Pro ($5/month) and Enterprise ($10/month) plans unlock additional features. The community is significantly smaller than Bruno, Hoppscotch, or Insomnia.

Best For

Teams building gRPC-first architectures. If gRPC is a secondary concern, Bruno or Hoppscotch will serve you better.

How to Choose the Right Postman Alternative

The decision comes down to three questions:

Where should your API data live? If the answer is "on my filesystem, in my Git repo, nowhere else" — Bruno is the obvious choice. If you want self-hosted cloud collaboration, Hoppscotch. If you need per-project flexibility between local and cloud, Insomnia.

How does your team collaborate? Git-based teams will thrive with Bruno's filesystem approach. Teams that want real-time editing and shared workspaces should look at Hoppscotch (self-hosted) or Insomnia (cloud sync). Solo developers can pick any option based on personal preference.

What protocols do you use? REST-only teams have the most choices. GraphQL narrows the field slightly but is well-supported by Bruno, Hoppscotch, and Insomnia. gRPC-heavy teams should evaluate Kreya first and Bruno second. WebSocket and MQTT testing points toward Hoppscotch.

For most teams migrating from Postman in 2026, start with Bruno if you value simplicity and privacy, or Hoppscotch if you value collaboration and a polished web UI. Both are MIT-licensed, actively maintained, and completely free.

Methodology

We evaluated each tool based on official documentation, GitHub repository activity, and community feedback. Criteria included: protocol support, offline capability, data storage and privacy model, licensing terms, collection management, environment variables, scripting support, team collaboration, and Git integration. We prioritized tools with OSI-approved open source licenses while including notable proprietary options where they fill gaps that open source tools do not yet cover. Star counts and release dates are current as of March 2026.

Find More Open Source Alternatives

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