Postman vs Insomnia vs Bruno: Choosing Your API Client in 2026

For a long time, the question of which API client to use barely needed asking. You installed Postman, you got on with your work. It was the default for building and testing HTTP APIs, with a feature set that covered everything from one-off requests through to automated test suites and mock servers.

That consensus has fractured. A wave of product decisions - forced cloud synchronisation, paywalled collaboration features, and mandatory account creation - pushed a significant portion of the developer community to look elsewhere. Insomnia, Bruno, and a handful of smaller alternatives absorbed that migration. Each has a different philosophy about how an API client should work, and the right choice genuinely depends on what your team needs.

This is our honest assessment of all three as developers who work with APIs every day.

What changed with Postman

Postman's trajectory from scrappy Chrome extension to enterprise API platform has been well documented. The tool that many developers fell in love with was local-first: collections lived on disk, requests ran without an account, and nothing required a network connection to your own tooling vendor. That changed progressively.

Postman now requires an account to use the desktop application. Collections are synchronised to Postman's cloud by default, with limited offline capability for free tier users. The free plan caps collaboration at three users, and team features - including role-based access to collections and environments - sit behind a paid tier. As of 2026 the pricing structure has evolved further toward enterprise, with per-seat costs that feel disproportionate for small agencies or independent contractors.

None of this is inherently wrong. Postman is a mature, well-funded product with genuine enterprise value. Its mock server, documentation generation, API monitoring, and contract testing features are best-in-class. For larger organisations with a budget, a security team that has reviewed data residency, and genuine need for the full collaboration suite, Postman still makes sense.

For smaller teams, contractors, and anyone uncomfortable with sensitive API credentials and request history living in a third-party cloud, the calculus changed.

Insomnia: the cautionary tale

Insomnia was the obvious beneficiary of Postman's drift. It was open-source, fast, and felt like the Postman of three years ago - clean interface, local storage by default, no forced account. It attracted a loyal following and a thriving plugin ecosystem.

Then Kong acquired it and made an almost identical set of mistakes. In 2023, Insomnia pushed an update that required users to log in and switched to cloud-synced storage. The backlash was immediate. The open-source community forked the last pre-cloud version into a project called Insomnium, which remains available but is not actively developed.

Kong subsequently softened the approach. The current version of Insomnia supports a local vault storage mode that keeps collections on disk without cloud sync. The damage to trust was done, though - the community's willingness to recommend Insomnia is still recovering from a decision that felt like a bait-and-switch.

Insomnia remains a capable tool. The UI is arguably the most refined of the three, the built-in testing capabilities are solid, and the plugin ecosystem - though smaller than Postman's - covers most common use cases. If the storage concerns are resolved to your satisfaction by the local vault mode, it is worth evaluating seriously. The uncertainty is whether Kong's product priorities will introduce similar friction again.

Bruno: the challenger

Bruno took a different architectural decision from the outset: collections are stored as plain text files on disk in a format called Bru, which is human-readable and designed to live in a git repository alongside the code it tests. There is no cloud sync, no account requirement, and no vendor infrastructure sitting between you and your request history.

This is not just a privacy argument. It is a workflow argument. When your API collections are files in your repository, they are versioned alongside the code, reviewed in pull requests, and branched with features. The question of which version of a collection matches which version of the API becomes a non-question - they are committed together.

The trade-offs are real. Bruno is younger than the other two and some rough edges are visible. The UI is functional rather than polished. The test runner and scripting support, while improving, is less mature than Postman's comprehensive assertion library. Documentation generation and mock server capabilities lag behind. The plugin ecosystem is smaller.

Bruno is also genuinely open-source under an MIT licence, which matters for organisations with strict procurement requirements. The project has attracted substantial community contribution and its development pace is fast. Features that were missing a year ago have arrived.

Feature comparison

Rather than an exhaustive feature matrix, here are the areas where the three tools diverge meaningfully:

Storage model: Postman stores collections in its cloud by default (offline available on paid plans). Insomnia offers local vault mode or cloud sync. Bruno stores everything as files on disk with no cloud option at all.

Git integration: Bruno is the only tool designed around git-native workflows. Postman and Insomnia both offer export and import, but collections are not first-class filesystem objects. Bruno's .bru files are.

Test scripting: Postman has the most mature test scripting environment, with Chai assertions, pre-request scripts, and a visual test builder. Bruno supports JavaScript test scripts and is improving; Insomnia supports scripting via plugins and built-in test runners.

Mock servers: Postman's mock server is genuinely useful for frontend-backend parallelism and contract testing. Bruno does not currently have a built-in mock server; this is typically handled externally. Insomnia has basic mock support.

Documentation: Postman generates API documentation automatically from collections and can publish it publicly. Bruno and Insomnia do not have equivalent built-in documentation publishing.

Collaboration: Postman's cloud sync is the foundation of its collaboration model - shared workspaces, team collections, role-based access. Insomnia offers similar features via cloud sync. Bruno's collaboration model is your git repository and whatever access controls you already have on it.

Protocol support: All three support REST and GraphQL. Postman and Insomnia both support WebSockets and gRPC. Bruno's WebSocket and gRPC support is in progress.

Cost: Bruno is free, open-source, no paid tier. Postman free tier is limited; team features require a paid plan. Insomnia has a free tier with local vault; cloud sync and team features require a paid plan.

Who should use what

The right choice is not universal. Here is how we think about it:

Use Bruno if your team works in git, you store your API specs in the repository, you have no interest in cloud sync, and your test scripting requirements are covered by JavaScript assertions. This is increasingly our default recommendation for development teams building APIs with Laravel or other backend frameworks. The workflow alignment is excellent.

Use Postman if you need the full enterprise feature set - mock servers, documentation publishing, automated monitoring, advanced contract testing, or deep collaboration features for a larger team. If your organisation has already standardised on Postman and has a paid plan, the switching cost is probably not justified unless the cloud sync issue is a genuine compliance concern.

Use Insomnia if you want a polished UI with local storage, your team is comfortable with Kong as a vendor, and you want plugin extensibility without Bruno's current rough edges. Watch how Kong's product decisions develop before committing.

Our current setup

At The API Guys, we have moved our day-to-day API development work to Bruno. The git-native model maps exactly to how we already work: branches for features, pull requests for review, collections committed alongside the route definitions they test. The lack of a built-in mock server is occasionally inconvenient but not a blocker - we handle that at the framework level or with lightweight tooling.

We still use Postman for specific client engagements where the client's team is already on Postman and documentation sharing is part of the deliverable. It remains the strongest option in that context.

Insomnia sits in between and has not found a clear role in our workflow. We respect what it offers, but the trust damage from the cloud sync episode still lingers - and Bruno has largely filled the gap that Insomnia was occupying.

The broader point

The API client space is a useful case study in what happens when tools that developers rely on are monetised in ways that erode the properties developers valued. Local-first, file-based, accountless tooling was never a premium feature - it was just how software used to work. Bruno is making the argument that it should still work that way.

Whether that philosophy scales into the enterprise features that larger teams need remains to be seen. But for the majority of development teams building and testing APIs in 2026, Bruno's model fits the workflow better than the alternatives, and the feature gaps are narrowing.

What is your team currently using, and has anything pushed you to switch in the last couple of years?