Advanced REST Client (ARC) is a free, open-source HTTP client for macOS that lets developers inspect, debug, and automate API calls without ever touching a browser.
What is Advanced REST Client?
Advanced REST Client is a native Electron-based desktop application built specifically for crafting and analysing HTTP requests against any REST, GraphQL, or raw HTTP endpoint. Unlike browser extensions that live and die with their host, ARC runs as a first-class macOS app — complete with its own window management, offline capability, and a persistent project store that survives browser updates.
The project is fully open-source, hosted on GitHub under the advanced-rest-client organisation, and has accumulated years of community contributions. I have been running it alongside paid tools like Paw and the ever-present Postman, and it holds its own for the daily grind of endpoint exploration.
What does Advanced REST Client do best?
ARC excels at raw request composition — it gives you granular control over headers, body encoding, authentication schemes, and redirect behaviour without burying those controls three menus deep. The request history panel is genuinely useful: every call you make is timestamped and saved locally, so when a colleague asks "what exact payload did you send last Tuesday?" you can pull it up in seconds rather than reconstructing it from memory.
Variable environments let you swap between dev, staging, and production base URLs with a single dropdown — a workflow that feels as snappy here as it does in Insomnia or Postman. The response viewer handles JSON, XML, binary blobs, and plain text gracefully, and the syntax-highlighted diff between two saved responses is the kind of small feature that saves real time during regression testing.
- Persistent local history — every request auto-saved, no cloud account required
- Environment variables for multi-stage API workflows
- Certificate management for mutual TLS endpoints
- Import/export of Postman and Swagger/OpenAPI collections
- WebSocket support alongside standard HTTP verbs
Is Advanced REST Client free?
Yes — ARC is completely free to download and use. There is no premium tier, no seat licence, and no usage cap. Because it is open-source (Apache 2.0 licence), you can also inspect every line of code that touches your API credentials, which matters more than most people admit when tokens for production systems are involved.
Who should use Advanced REST Client?
ARC is a strong fit for backend engineers and QA testers who want a capable HTTP client that does not require a cloud account or a corporate subscription to unlock core features. If your team is allergic to Postman's telemetry, or if you simply want a lightweight tool for personal projects, ARC delivers the essentials without the overhead.
It is less ideal if your workflow centres on slick collaboration features — shared workspaces, inline commenting on requests, or real-time sync across machines. For those scenarios, Paw (now RapidAPI for Mac) or Insomnia's cloud tier serve better. ARC is fundamentally a personal-machine tool, and it owns that role confidently.
How does Advanced REST Client compare to Postman?
Postman has matured into a full API platform with mock servers, monitors, and a publishing pipeline. That breadth comes at a cost: a mandatory account, background telemetry, and an interface that can feel bloated when all you want to do is fire a single authenticated GET. ARC strips that away. The trade-off is real — you lose Postman's team collections and its vast public API network — but you gain a tool that starts in under two seconds, stores everything locally, and never prompts you to upgrade.
Against Insomnia, ARC is roughly equivalent in feature depth for solo use, though Insomnia's plugin ecosystem is more active. Against HTTPie Desktop, ARC's GUI is more form-centric while HTTPie leans toward a CLI-adjacent feel. Neither is objectively superior; it depends on how you think about requests.
What are the best Advanced REST Client alternatives?
The honest list: Postman for teams and mock-server workflows, Paw / RapidAPI for a native-first macOS experience with code generation, Insomnia for a clean mid-ground with GraphQL support front and centre, and HTTPie Desktop if you prefer a terminal-inspired aesthetic. For purely CLI work, curl and httpie (command-line) remain unbeatable. ARC sits in the free-and-local corner of this map, and that corner has a devoted audience.
