Why Kong Insomnia Is Developers' Preferred API Client

August 8, 2025

7 min read

Juhi Singh

Technical Product Marketing Manager, Kong

Explore the developer-focused features of Kong Insomnia: local-first storage, built-in Git sync, and a powerful offline CLI for automated workflows

Picture this: you’re in the zone — debugging logic, writing endpoints, testing integrations. But suddenly you’re yanked out of flow: copy pasting cURL commands, flipping between environments, chasing down the right API keys, and juggling half a dozen tools just to make a simple change. It’s clunky and error-prone. And honestly, it’s not what you signed up for.

Modern API workflows shouldn’t feel like duct-taping tools together. They should be seamless, automated, and built to move at the speed of development. That’s where Kong Insomnia comes in. It’s more than just an API client; it is an open-source desktop application that simplifies designing, mocking, debugging, and testing APIs. Insomnia combines an easy-to-use interface with advanced functionality, like authentication helpers, code generation, and environment variables.

In this blog, we’ll walk through a practical API lifecycle using Insomnia and break down six reasons why developers trust it as their API client of choice.

So, what exactly is Kong Insomnia?

Kong Insomnia is your all-in-one platform for designing, testing, debugging, and shipping APIs at speed. Built for developers who need power without bloat, Insomnia helps you move fast whether you’re working solo, scaling a startup, or collaborating across enterprise teams. With real-time collaboration and enterprise-grade security baked in, Insomnia brings the entire API lifecycle into a single streamlined experience, keeping your workflows tight, your specs accurate, and your productivity on point. You can design, mock, test, and debug without leaving your flow and only by using a single tool.

6 reasons why developers prefer Insomnia

Picking the right API client is about finding the right fit for the way you work. With that in mind, here are six reasons developers love Insomnia.

1. Control your data with local storage and Git Sync

Insomnia puts you in the driver’s seat when it comes to data storage. Everything, starting from requests and environments to tests and design specs, lives locally by default. No auto sync, no forced cloud. Just fast, reliable access with full offline support, local backups, and instant recovery.

For version control, simply point Insomnia to a Git repository. You can treat your API projects like any other codebase: branch, commit, create pull requests, and roll back changes. It fits right into your existing GitOps workflow. When you need to collaborate, enable optional Cloud Sync with end-to-end encryption for secure teamwork. You get shared access without sacrificing on security.

Whether you're flying solo, collaborating with a team, or integrating with CI/CD, Insomnia is flexible by design: local-first, Git-native, and cloud-optional.

2. A clean, developer-focused UI

Insomnia’s interface is designed for developers who want to move fast and stay in flow. There is no clutter, no distractions — just a clean, single pane layout that puts your requests, environments, tests, and specs right where you need them.

Every element is thoughtfully placed for speed and clarity, minimizing clicks and context switches. Kong Insomnia feels more like a power tool than a platform: snappy, predictable, and optimized for muscle memory.

This isn’t a bloated enterprise dashboard. It's a developer-first workspace that behaves like an extension of your IDE. If you live in VS Code or the terminal, you’ll appreciate how seamlessly Insomnia fits into your stack.

3.APIs as code, built right in

Insomnia doesn’t just support Git, it embraces it. If your team already versions everything in Git, your API workflow shouldn’t be any different. With native Git Sync, you can treat your API specs, collections, and test suites as first class code assets: committed, branched, and merged just like the rest of your stack.

Need to prototype a new endpoint or refactor an existing one? Create a feature branch directly from the Insomnia UI, without risking production workflows. When your changes are ready, push them and open a pull request. Insomnia provides a clear diff that your team can review, comment on, and approve like any other code change. You can even resolve merge conflicts within the app.

But the real power shows up when you plug it into your CI/CD pipeline. Run validation checks, auto-trigger contract tests, lint your OpenAPI specs, or even push updates to your documentation with every merge. With Git as a single source of truth, you get full traceability, clean version history, and bulletproof collaboration — no manual exports, no tool sprawl.

It’s APIs as code, done the right way: clean, consistent, and purpose-built for developer workflows.

4. CLI power, without the cloud dependency

Modern API development thrives on automation, and Insomnia’s Inso CLI delivers exactly that, without tying you to the cloud. Whether you're linting OpenAPI specs, running tests, exporting configs, or validating API contracts, Inso works directly with your local files.

It fits seamlessly into real developer workflows: hook it into CI/CD pipelines (like GitHub Actions, GitLab, Jenkins, Vercel, and more), or run it locally as part of your pre-commit process. Automate regression tests, validate specs before deploys, and keep your APIs production-ready on your terms.

Example for our Accounts API

Simple, fast, and script-friendly, everything you expect from a CLI built for real-world developers' workflows.

5. Unlimited collection runs, built for real-world dev work

Testing isn't nice to have: it's a core part of API development. Whether you’re iterating on a new feature, building out test coverage, or plugging into a CI/CD pipeline, you’ll need a tool that lets you run collections freely, without limits or hidden costs. That’s exactly what Kong Insomnia does.

With unlimited local collection runs, you can test as often as your workflow demands. No throttling, no usage caps, no surprise paywalls. It’s ideal for fast-moving developers who ship often and need the freedom to run full test suites, validate edge cases, or just keep hammering away until the response is perfect.

For quick, one-off requests, Scratch Pad mode lets you make API calls instantly, no account, no project setup, no friction. It's perfect for those spontaneous "I just need to hit this endpoint" moments. Insomnia is built for how developers actually work: it removes friction, respects your momentum, and gives you complete testing power without holding anything back.

6. Open source and extensible

Insomnia isn't a black-box tool you must adapt to; it's an open-source platform (MIT licensed) that you can shape. You’re not just a user; you’re part of a developer-driven ecosystem that evolves to meet real-world needs.

Need to tweak Insomnia to fit your stack? No problem. With 350+ community-built plugins, chances are someone’s already built the functionality you’re looking for; whether it's a custom auth flow, request visualizer, data generator, or even a theme that matches your vibe. And if not? Roll your own. The plugin system is built to be approachable and flexible, making it easy to extend Insomnia with JavaScript and Node.js.

Kong Insomnia gives you the flexibility to shape your workflow, not the other way around. It's a tool that grows with you from quick one-off requests to deeply customized setups across teams.

Insomnia vs. Postman

When it comes to choosing the right API tool, the key difference between Insomnia and Postman boils down to developer control.

Kong Insomnia is designed to give you complete control. Your data is saved locally by default, no surprise uploads, no forced cloud sync. That means you own your workflows, your API collections, and your environment data, right on your machine.

In contrast, Postman is deeply integrated with the cloud. While this approach can benefit teams needing centralized access, it can feel restrictive for developers who handle sensitive data, prioritize offline work, or simply prefer to manage their own environments. This philosophical difference extends directly to the user experience. Insomnia maintains a lean, focused, and fast UI, allowing you to test, debug, and iterate efficiently.

If your workflow revolves around Git, the terminal, and automation, Kong Insomnia will feel instantly familiar. It comes with native Git support, a cloud-optional CLI, and a mindset that treats your APIs like code, from version control to CI/CD testing. Postman can support similar workflows, but it tends to funnel you back through its cloud-based platform to do so. And here’s a major win for developers: Insomnia is open-source and unlimited. You can extend it, inspect it, or tailor it to your stack. Want to run test suites locally a hundred times a day? Go for it, no paywalls, no limits. With Postman, that same flexibility often comes at a cost.

In short, if you want a tool that feels like it was built for how modern devs work offline-first, Git-native, scriptable, and fully customizable, Kong Insomnia is the one to beat.

Final thoughts: Insomnia is built for developers who build differently

Picking an API client isn’t just about features; it's about choosing the right fit. The right tool should match the way you work. If you care about keeping your data local, treating your API specs like source code, and automating the boring stuff through your CI/CD workflows, Kong Insomnia is a natural choice.

It’s not just open source, it's open to how you work. You’re not locked into cloud-first workflows or arbitrary usage limits. Instead, you get full control over your environment, native Git integration, a powerful CLI for automation, and a vibrant plugin ecosystem — all with a lightweight interface that gets out of your way and helps you stay in flow.

Whether you're a solo dev, part of a startup team, or contributing to a large-scale enterprise pipeline, Kong Insomnia scales with your needs. And because it’s built by developers who actually use it, every detail feels intentional; no clutter, no fluff, just what you need to ship great APIs, faster.