API testing tools range from GUI-heavy collaboration platforms to CLI-native text-based testers. Postman, Insomnia, Bruno, and Hurl each serve different workflows. Here's which one matches how you develop and test APIs.
Quick Comparison
| Postman | Insomnia | Bruno | Hurl | |
|---|---|---|---|---|
| Type | GUI + cloud sync | GUI + local/cloud | GUI + Git-native (files) | CLI (text files) |
| Storage | Postman Cloud | Local or Insomnia Cloud | Local files (plain text) | .hurl files (plain text) |
| Version control | Postman workspaces | Git sync (collections) | Git-native (folder of files) | Git-native (.hurl files) |
| Collaboration | Excellent (workspaces, comments) | Good (Insomnia Cloud) | Via Git (PR reviews) | Via Git (PR reviews) |
| Free tier | Limited (3 collaborators) | Generous (local + git) | Open source (MIT) | Open source (Apache 2.0) |
| GraphQL | Yes | Excellent (native) | Yes | Yes |
| gRPC | Yes (beta) | Yes | No | No |
| Scripting | JavaScript (pre/post scripts) | Plugins (JS) | Scripting (JS) | Assertions in .hurl |
| CI/CD integration | Newman (CLI runner) | Inso (CLI) | Bruno CLI | Native CLI (single binary) |
Postman — The Industry Standard (With Strings Attached)
Postman is the most popular API testing tool with 30M+ users. Its GUI is polished, collaboration features are excellent, and it supports every API protocol. The downside: collections live in Postman's cloud, and the free tier has been steadily shrinking.
Strengths: Polished GUI with excellent UX. Best-in-class collaboration (workspaces, comments, forking). Supports REST, GraphQL, gRPC, WebSocket, MQTT. Newman for CI/CD. Massive community and documentation. Mock servers for testing.
Weaknesses: Free tier limited to 3 collaborators. Collections are cloud-locked (vendor lock-in). Account required for core features. GUI is heavy (slow startup). Pricing has steadily increased. Not Git-friendly by default.
Best for: Teams that need collaboration, organizations already using Postman, developers who prefer GUI over CLI, API-first companies with dedicated API teams.
Insomnia — The Open-Source Alternative
Insomnia started as an open-source Postman alternative. It supports REST, GraphQL (with excellent schema introspection), and gRPC. Collections can be stored locally or in Insomnia Cloud. The GraphQL support is better than Postman's.
Strengths: Excellent GraphQL support (schema introspection, autocomplete). Local-first (collections are files). Good UI/UX (simpler than Postman). Inso CLI for CI/CD. Better free tier than Postman. Works offline.
Weaknesses: Smaller community than Postman. Collaboration requires Insomnia Cloud (paid). Some features have moved to paid tier. Less third-party integration support. gRPC support is newer.
Best for: GraphQL APIs, developers who prefer local-first tools, solo developers and small teams, offline API development.
Bruno — The Git-Native Challenger
Bruno is the newest entrant and takes a radical approach: collections are folders of plain-text files, designed to be stored in Git. No cloud account required. No vendor lock-in. Every request is a .bru file that can be reviewed in a PR.
Strengths: True Git-native workflow (collections are text files). Open source (MIT). No account required. Collections work offline forever. PRs for API changes make sense to developers. Lightweight and fast. No vendor lock-in.
Weaknesses: Newest tool (smaller community). No built-in collaboration (Git is the collaboration). Fewer protocol support (no gRPC yet). Less polished than Postman. Fewer integrations.
Best for: Git-centric teams, open source projects, developers who want plain-text ownership, teams that want API tests reviewed in PRs.
Hurl — The CLI-Native Power Tool
Hurl is a command-line tool that runs API tests defined in .hurl files — a simple text format combining HTTP requests with assertions. It's incredibly fast, works anywhere, and is perfect for CI/CD pipelines. Think of it as "curl with assertions in a file."
Strengths: Extremely fast (compiled binary). Simple, readable .hurl format. Perfect for CI/CD (single binary, no dependencies). Excellent for smoke tests and health checks. Captures and reuses values across requests. HTML/JSON/XML assertion support. Open source.
Weaknesses: No GUI (CLI only). Not for exploratory testing (design requests in a GUI first, then write .hurl). Smaller community. Less intuitive for non-CLI developers. No GraphQL schema introspection.
Best for: CI/CD pipeline testing, API smoke tests, developers who prefer CLI, automated testing of deployed environments, complementing a GUI tool (design in Postman/Bruno, automate in Hurl).
The API Testing Stack
| Need | Best Tool |
|---|---|
| Team collaboration on API design | Postman |
| GraphQL development | Insomnia |
| Git-native, no vendor lock-in | Bruno |
| CI/CD automation and smoke tests | Hurl |
| Solo developer, quick testing | Bruno or Insomnia |
Bottom line: Bruno + Hurl is the modern, Git-friendly stack — design requests in Bruno, automate in Hurl. Postman is still the default for team collaboration but comes with lock-in. Insomnia for GraphQL. See also: REST API Best Practices and tRPC vs GraphQL vs REST.