Postman vs Insomnia vs Thunder Client: Which API Client Is Best for Developers in 2024

Postman vs Insomnia vs Thunder Client: Which API Client Is Best for Developers in 2024

A 2023 Postman survey of more than 40,000 developers found that API work now consumes roughly half of a typical developer’s week. Whether you’re debugging a REST endpoint, testing a GraphQL query, or wiring up a webhook, the tool you reach for matters more than most teams admit. Three names dominate the conversation in 2024: Postman, Insomnia, and Thunder Client. Each has a distinct philosophy, and the “best” one depends heavily on how you work.

This comparison breaks down features, pricing, performance, and real-world tradeoffs so you can pick the right client without wasting a sprint on tooling debates.

The Contenders at a Glance

Postman launched in 2012 as a Chrome extension and has grown into a full API platform. It handles design, testing, mocking, documentation, and monitoring. It’s the default choice at most enterprises.

Insomnia, now owned by Kong, started as a lean REST and GraphQL client with a reputation for speed and a clean interface. It has expanded into design and testing features while keeping a lighter footprint.

Thunder Client is a VS Code extension built by Ranga Vadhineni. It lives inside your editor, weighs almost nothing, and targets developers who don’t want to context-switch.

Feature Depth: Postman Leads, But You May Not Need It

Postman’s feature set is genuinely enormous:

• Collection runner with scripting in JavaScript
• Pre-request and test scripts with a built-in assertion library
• Mock servers generated from schemas
• API documentation that publishes to a public URL
• Monitors that run collections on a schedule
• A CLI (Newman) for CI/CD pipelines
• Workspace collaboration with role-based access

If your team needs contract testing, scheduled monitoring, or a shared API catalog, Postman is hard to beat. The catch is that this surface area comes with a learning curve. New users often report that simple tasks feel buried under menus.

Insomnia covers the essentials well: environments, variable chaining, code generation, and a plugin ecosystem. Its GraphQL support is arguably the best of the three, with schema introspection and autocomplete that feel native. Insomnia also supports gRPC and WebSockets cleanly. What it lacks is Postman’s depth in automated testing and monitoring.

Thunder Client is deliberately minimal. You get request building, environments, collections, and basic test scripts. It supports GraphQL and can run collections, but there’s no mock server, no monitoring, and no hosted documentation. For solo developers or small teams testing endpoints during development, that’s often enough.

Performance and Resource Usage

This is where the tools diverge sharply.

Postman is an Electron app. On a mid-range machine, it commonly idles at 400–700 MB of RAM, and memory use climbs with large collections. Users with dozens of open tabs have reported spikes above 1 GB.

Insomnia is also Electron-based but historically leaner, typically idling in the 200–400 MB range. Kong has added features over time, so the gap has narrowed, but Insomnia still feels faster to launch and navigate.

Thunder Client runs inside VS Code, which means it adds only a small increment to an editor you already have open. If VS Code is already consuming 500 MB, Thunder Client might add 50–100 MB. For developers on constrained hardware or those who hate running five Electron apps at once, this is a meaningful advantage.

Pricing: The 2024 Landscape

Pricing changed significantly in 2023, and it’s worth getting the numbers right.

Postman offers a free tier for individuals with limited collection runs and no collaboration. Paid plans start around $14 per user per month (billed annually) for the Basic tier, with Professional at roughly $29 and Enterprise at $49. Prices vary by region and seat count, so check the current pricing page.

Insomnia moved to a tiered model after Kong’s acquisition. The free plan covers most individual use. Individual paid plans run about $12 per month, and team plans start around $24 per user per month. There’s also an Enterprise tier with SSO and audit logs.

Thunder Client is free for individual use with a generous feature set. A paid plan (around $5–6 per month) unlocks team collaboration, unlimited collection runs, and priority support. For the price, it’s the cheapest way to get a functional API client with team features.

Collaboration and Team Workflows

Postman’s collaboration tools are its strongest moat. Shared workspaces, comments, version history, and role-based permissions make it viable as a team’s single source of truth for API definitions. If your organization already uses Postman, switching costs are real.

Insomnia supports team workspaces and Git sync, which appeals to teams that want API specs versioned alongside code. The Git integration is a genuine differentiator for developer-centric workflows.

Thunder Client’s team features are newer and simpler. You can share collections and sync via a paid plan, but it doesn’t attempt to be a collaboration platform. It’s a tool for individuals and small teams, not a replacement for a company-wide API hub.

Which One Should You Actually Use?

The honest answer depends on your context:

Choose Postman if you work on a team that needs shared collections, automated tests, monitoring, and documentation in one place. The overhead is worth it at scale.

Choose Insomnia if you value a faster, cleaner interface, work heavily with GraphQL or gRPC, and want Git-based workflows without Postman’s weight.

Choose Thunder Client if you live in VS Code, mostly test endpoints during development, and don’t need enterprise collaboration or monitoring. The zero-context-switch workflow is its killer feature.

Many developers use more than one. A common pattern is Thunder Client for quick in-editor checks and Postman or Insomnia for deeper debugging and team-shared collections.

A Note on Lock-In

One practical consideration: collections don’t always port cleanly between tools. Postman can import Insomnia and OpenAPI files, and Insomnia can import Postman collections, but scripts and environment variables often need manual fixes. If you’re evaluating tools, export your existing collections first and test the import before committing.

The Bottom Line

There’s no single winner in 2024. Postman remains the most capable platform and the safest bet for teams. Insomnia offers a leaner experience with strong GraphQL and Git support. Thunder Client wins on speed, price, and editor integration for individual developers.

Pick based on your workflow, not on feature checklists. If you spend your day in VS Code and rarely share collections, Thunder Client will make you faster. If your team needs a shared API workspace with monitoring, Postman earns its resource cost. And if you want something in between, Insomnia sits comfortably there. Try all three for a week each—the right choice usually becomes obvious within a few days of real work.