API Testing
An honest comparison to help you pick the right api testing tool in 2026.
| Feature | Insomnia | Thunder Client |
|---|---|---|
| Category | API Testing | API Testing |
| Free Tier | Yes | Yes |
| Paid Plan | $5/mo | $3/mo |
| Enterprise | $14/mo | Custom |
| Best For | API developers who work heavily with GraphQL and want git-synced API workspaces | Developers who want to test APIs inside VS Code without switching to a separate desktop app |
| Feature 1 | GraphQL support | Native VS Code extension |
| Feature 2 | Design-first | Collections & environments |
| Feature 3 | Git sync | Scriptless testing |
| Feature 4 | Environment management | Git-syncable collections |
| Feature 5 | Plugin ecosystem | Lightweight |
| Website | Insomnia | Thunder Client |
Insomnia and Thunder Client are both popular choices in the api testing category, but they serve different types of developers. Insomnia is aPI client with GraphQL support, design-first workflows, Git sync, and environment management for API development. Meanwhile, Thunder Client is lightweight API client built directly into VS Code, with collections, environments, and scripting without leaving the editor.
Both tools offer free tiers, which means you can try each one before committing. Insomnia's paid plan starts at $5/mo, while Thunder Client's starts at $3/mo.
Insomnia stands out with GraphQL support and Design-first, while Thunder Client differentiates itself through Native VS Code extension and Collections & environments. The right choice depends on which capabilities matter most for your workflow. Ultimately, aPI developers who work heavily with GraphQL and want git-synced API workspaces, while Thunder Client is best for developers who want to test APIs inside VS Code without switching to a separate desktop app.
Insomnia: Free tier available. Paid plans start at $5/mo. Enterprise pricing: $14/mo.
Thunder Client: Free tier available. Paid plans start at $3/mo. Enterprise pricing: Custom.
Choose Insomnia if you value graphql support and design-first. Go with Thunder Client if developers who want to test APIs inside VS Code without switching to a separate desktop app. Both are solid api testing options in 2026 — the best pick depends on your team size, budget, and technical requirements. We recommend trying both (especially if they have free tiers) before committing to one.
Not sold on either Insomnia or Thunder Client? Check out these other api testing tools:
See all Insomnia alternatives or Thunder Client alternatives.
Read more about api testing on our Vibe Coding page.
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