Best Postman Alternatives in 2026: Free, Open-Source and Local-First API Testing Tools

The best Postman alternatives are Bruno if you want a local-first client that keeps collections in Git, Hoppscotch if you want an open-source tool in the browser or on your own server, and Insomnia if you want a familiar desktop client from Kong. Thunder Client fits people who want requests inside VS Code, and Apidog suits teams that want design, testing and mocking in one hosted workspace.

Postman is a commercial API platform with a desktop client, collections, mock servers, monitoring and AI features. This guide starts with API clients, then covers the best API testing tools and free options for automated tests. Licences and pricing models are given as Enlisted lists them.

Why people look for Postman alternatives

Postman is a closed-source platform for designing, testing, documenting and monitoring APIs. The reasons to look elsewhere are specific.

• Sign-in for saved work. Postman's docs say its lightweight API client lets you build and send requests without signing in, with the work stored locally. Saving requests to collections and using environments and variables needs a signed-in workspace.
• A free plan for one person. Postman's pricing page lists the Free plan for one user, with monthly limits on items such as Postman API calls and AI credits. Team collaboration sits on the paid Team plan.
• A large platform. Beyond the client it covers design, mock servers, monitoring, a catalogue and governance. If you only send requests and run tests, that is more than you need.
• Closed source, cloud-hosted. Enlisted lists Postman as proprietary with no self-hosted version, so there is no way to run it on your own servers.
• Collections as files. Tools such as Bruno and Resterm keep requests as plain text files you can diff and review in pull requests, which some teams prefer to a workspace in a vendor's cloud.

How we picked

Each tool sends and inspects API requests and organizes them into collections, which is Postman's core job. For open-source tools Enlisted checks recent GitHub activity and the licence, and for closed ones the free plan and pricing model. Where a tool's repository has not been updated recently, we say so. Descriptions come from the catalogue and vendor docs, and the method is explained in how Enlisted ranks tools.

1. Bruno: best local-first, Git-friendly client

Bruno is an open-source API client for REST, GraphQL, gRPC and WebSocket that stores collections as plain text files in a folder on your filesystem. Where Postman keeps work in workspaces, Bruno saves each request in a markup language called Bru, so you can version and share collections with Git or any version control system you already use.

It is offline only, and its maintainers state they have no plans to add cloud sync. A CLI runs collections for automated testing in CI/CD, and a Docker option is documented. Bruno's docs describe importing Postman collections exported as v2 or v2.1 JSON, translating common script calls such as pm.test and pm.environment. The core is MIT-licensed, with paid Pro and Ultimate tiers.

• Best for: teams that want API collections stored next to code and reviewed in pull requests.
• Watch out for: there is no cloud workspace, so sharing happens through Git, and some features such as bulk import sit in a paid tier.

2. Hoppscotch: best open-source client in the browser or on your own server

Hoppscotch is an open-source API development tool for REST, GraphQL and WebSocket requests that runs in the browser, as a desktop app and from a command line. It is positioned as an alternative to Postman and Insomnia, with offline, on-premises and cloud options.

The request builder generates code snippets for more than ten languages and frameworks, shares requests through public URLs, and installs as a progressive web app for offline use. It is released under MIT, with a hosted version at hoppscotch.io.

• Best for: developers who want a lightweight, open-source client with a web app and the option to self-host.
• Watch out for: Enlisted's listing mentions on-premises options but does not flag it as self-hostable, so confirm the setup you need on its site.

3. Insomnia: best familiar desktop client with local, Git or cloud storage

Insomnia is an open-source API client from Kong that handles GraphQL, REST, WebSockets, Server-Sent Events and gRPC. Like Postman it also covers design and testing: an OpenAPI editor with visual preview, test suites, a collection runner and mock servers, plus a CLI for linting and testing in CI/CD.

The storage choice is the main difference. Projects can live in a Local Vault for fully local use, sync through any Git repository, or sit in the cloud with optional end-to-end encryption. It is Apache-2.0 licensed. Enlisted lists a free Essentials plan and paid Pro and Enterprise plans, and a free local-only Scratch Pad.

• Best for: teams that want a full-featured desktop client, with design and testing, and a choice of where data lives.
• Watch out for: the free Essentials plan has limits, so compare it with the paid tiers on its pricing page before rolling it out to a team.

4. Yaak: best fast desktop client for privacy-minded developers

Yaak is a desktop API client for REST, GraphQL, gRPC, WebSocket and Server-Sent Events, built with Tauri, Rust and React. It works offline-first, with no telemetry and no requirement to sync data to a cloud account.

It imports collections from Postman, Insomnia, OpenAPI, Swagger or curl, supports OAuth 2.0, JWT and Basic Auth, and can keep encrypted secrets in the operating system keychain. Workspaces mirror to Git-friendly files. The code is MIT-licensed.

• Best for: developers leaving Postman or Insomnia who want a fast, local client.
• Watch out for: it is free for personal use only, and commercial use needs a paid licence.

5. Thunder Client: best for testing inside VS Code

Thunder Client is a lightweight REST API client that runs as an extension in VS Code and JetBrains IDEs, so you can send requests without leaving the editor. It also supports GraphQL queries.

Client data is stored locally, collections can be saved to a Git repository for sharing, and responses can be tested through a GUI without writing scripts. A command line interface is available. Enlisted lists a free tier for the VS Code extension and paid per-user plans.

• Best for: developers who live in VS Code and want requests next to their code.
• Watch out for: it is proprietary, and you depend on an editor extension rather than a standalone app.

6. Apidog: best hosted all-in-one for design, testing and mocking

Apidog is a commercial tool that brings API design, request debugging, automated testing and mock servers into one workspace. It is aimed at developers and QA engineers who use a separate API client, documentation tool and mock server.

Enlisted lists a free plan. The vendor describes capabilities and plans on its own site, so confirm limits there.

• Best for: teams that want one hosted tool across the API lifecycle.
• Watch out for: it is closed source and hosted, so it does not answer a request for local-only or self-hosted tools.

7. Requestly: best Git-native client from a closed-source vendor

Requestly API Client is a tool for designing, building and testing APIs, positioned as a privacy-first alternative to Postman. The public GitHub repository is a community hub for bugs and the roadmap, and its README states the application itself is closed source.

It offers a REST playground, pre and post scripts, GraphQL with schema introspection, Git sync for collections, and local workspaces stored as files. You can import from cURL, Postman and OpenAPI, and choose local, team sync or self-hosted setups.

• Best for: teams that want a Postman-style client with Git sync and local workspaces.
• Watch out for: the app is not open source, and Enlisted lists no free plan, only a free start.

8. Scalar: best for OpenAPI documentation plus an offline client

Scalar is an open-source API platform built around OpenAPI. One part turns OpenAPI or Swagger documents into an interactive API reference with a built-in testing tool and generated code samples. The other is an offline-first API client that treats OpenAPI and Swagger as first-class inputs.

It integrates with server frameworks such as Hono, FastAPI and Elysia, and a watch mode keeps the client in sync with a running server. The code is MIT-licensed, with a free plan limited by the number of APIs and paid plans above it.

• Best for: teams that publish OpenAPI docs and want a client that works from the same spec.
• Watch out for: it is spec-first, so it suits OpenAPI-based teams more than people who send ad hoc requests.

9. Kreya: best desktop client for gRPC and file-based collections

Kreya is a privacy-first desktop client for gRPC, REST, GraphQL, WebSocket and Server-Sent Events, with data kept on your device rather than in a vendor cloud. Requests, collections and settings are stored as plain files that diff cleanly, so a team can review them through Git.

It can watch OpenAPI specs, GraphQL schemas and protobuf files, supports gRPC server reflection, and runs automated tests with snapshots and scripts in CI. Kreya is proprietary software that you can download for free, with a free plan for individuals and paid Pro and Enterprise plans.

• Best for: developers who work with gRPC and want local, file-based collections.
• Watch out for: it is closed source, and the page does not tie specific prices to its paid plans.

10. HTTPie: best for quick requests from the terminal or a lightweight app

HTTPie Desktop is a graphical client for REST, GraphQL and general HTTP APIs from the team behind the HTTPie command-line tool, with releases for macOS, Windows and Linux and a companion web app. The repository lists its licence as Other, so check the terms.

The HTTPie CLI is a separate BSD-3-Clause command-line client with a short, natural syntax, built-in JSON support and colorized output. Its repository's latest commit is older than most tools in this guide, so check its activity before relying on it.

• Best for: quick, readable requests from the terminal, or a simple graphical client.
• Watch out for: it is a client, not a testing or collaboration platform.

11. ATAC: best terminal-based client

ATAC, short for Arguably a Terminal API Client, is a text user interface written in Rust for building and sending API requests, similar in spirit to Postman, Insomnia and Bruno but entirely in the terminal. It works over SSH, has Vim key bindings and NeoVim integration, and is MIT-licensed.

Another terminal option is Resterm, an Apache-2.0 client that stores requests as plain .http files with workflows, mocks and a CI runner.

• Best for: keyboard-focused developers and remote sessions.
• Watch out for: there is no graphical interface, so it suits terminal users only.

Best API testing tools and free API testing tools

An API client sends requests by hand. An API testing tool runs assertions automatically on every commit. Many teams use both, and the clients above already include some automation.

• Command-line runners for your client. Bruno's CLI runs collections for CI/CD, Insomnia has a CLI for linting and testing in pipelines, and Hoppscotch offers a CLI. If you already chose one of these clients, start here.
• Karate: an MIT-licensed framework that brings API tests, mocks, performance tests and UI automation together. Tests are readable feature files, so people who are not Java developers can write them.
• Step CI: an MPL-2.0 framework that tests REST, GraphQL, gRPC, tRPC and SOAP APIs from YAML, JSON or JavaScript workflows, with migration guidance from Postman and Insomnia. Its repository's latest commit is older than most tools here, so check its activity.
• Newman: Postman's command-line collection runner for CI, now in maintenance mode.
• k6 and Apache JMeter: open-source load-testing tools, k6 under AGPL-3.0 with JavaScript tests and JMeter under Apache-2.0.
• Mockoon: a free, MIT-licensed desktop app and CLI for running mock REST APIs locally, with a Docker image for CI.

For free API testing, the open-source tools cost nothing to install, and several clients have free plans. Check licences first: Yaak needs a paid licence for commercial use, and Requestly's app is closed source.

Which Postman alternative should you choose?

See every Postman alternative in the catalogue, the Thunder Client alternatives page, or the API tools category.

Moving off Postman: what to check

Before you switch, list what you rely on besides sending requests: shared workspaces, environments, pre-request scripts, monitors and mock servers. Most clients import collections, but scripts and variables are the parts that usually need fixing. Store collections in Git where you can, and pick a client your whole team can use, since a split team ends up with two sets of collections.

If you keep your collections in a repository, the host matters too; see the GitHub alternatives guide. If you build internal tools that call APIs, the Retool alternatives guide covers that side.