Insomnia is an open-source, cross-platform API client owned by Kong Inc. — the company behind the Kong API Gateway. Originally an independent project beloved for its clean, distraction-free interface, Insomnia was acquired by Kong in 2019 and has since evolved into a full API development platform with design, testing, mocking, and CI/CD pipeline capabilities. It is MIT-licensed at its core and available on macOS, Windows, and Linux.

What sets Insomnia apart from Postman is its flexible storage model: you can keep everything 100% local via Local Vault, sync through any third-party Git repository without touching Insomnia's cloud, or use Insomnia Cloud Sync for team collaboration — and mix these per project. This makes it the middle path between Bruno's hard offline-only stance and Postman's default cloud-everything approach. Insomnia is also the strongest tool in this category for GraphQL, with first-class schema introspection, query autocompletion, and explorer built in.

Key Features

Flexible Storage Model — choose Local Vault (fully offline), Git Sync (any third-party Git provider, no cloud), or Cloud Sync per project. Private Environments are always stored locally regardless of project storage choice, so secrets never leave your machine.
Broadest Protocol Support — REST, GraphQL, gRPC, WebSockets, Server-Sent Events (SSE), and SOAP all supported natively, making it the most protocol-complete client in its class.
First-Class GraphQL — schema exploration, autocompletion, and real-time linting make it the preferred choice for GraphQL-heavy teams over both Postman and Bruno.
OpenAPI Design Mode — a dedicated Design tab with real-time OpenAPI spec linting and visual preview lets you design APIs before implementing them, with seamless hand-off to the Debug/Test workflow.
Native Test Suites & Inso CLI — write assertions in JavaScript using Chai.js syntax, run full test suites with a single click or via the inso CLI, and plug directly into CI/CD pipelines without extra configuration.
Mock Servers — create local or cloud-hosted mock servers from design documents to enable parallel frontend-backend development without a live backend.
MCP Client & AI Runner — native MCP client for testing MCP servers, plus an AI Runner that lets developers consume LLMs supported by the Kong AI Gateway directly from within Insomnia.
Plugin Ecosystem — extend functionality with community plugins; the open-source core means custom integrations are straightforward to build and maintain.

Why Choose Insomnia?

Insomnia is the strongest choice for teams that want more flexibility than Bruno's no-cloud stance but a cleaner, lighter experience than Postman's everything-platform approach. It is the go-to for GraphQL-heavy workflows, teams that want Git-native version control without being forced fully offline, and organizations already in the Kong ecosystem. The free Hobby plan covers all core features for unlimited collaborators on one project; paid plans unlock multi-project collaboration, RBAC, and enterprise SSO.

API Development Mac Apps

Insomnia

Bruno

Postman

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