The REST Client That Respects Your Privacy and Your Time
RESTK is a powerful native REST client for macOS and Windows. Build, send, and debug HTTP requests with a fast, offline-first tool that stores everything locally and never forces you into the cloud. No account required. No telemetry. Just a fast, capable REST client that works.
Free forever for individual developers. No sign-up required.
Every HTTP Method, Full Control
RESTK supports every standard HTTP method and lets you define custom methods for non-standard APIs. Each request type gets full access to headers, authentication, body configuration, and scripting.
Retrieve resources from an API endpoint. Fetch data without modifying server state.
Create new resources. Send JSON, form data, binary files, or GraphQL queries.
Replace an entire resource. Full updates where the request body replaces the existing record.
Partial updates. Modify specific fields on a resource without replacing the whole object.
Remove resources. Send delete requests with optional body payloads and authentication.
Check response headers without downloading the body. Useful for cache validation and content negotiation.
CORS preflight requests. Discover which methods and headers an endpoint supports.
Define custom HTTP methods for non-standard APIs. Full flexibility for any protocol requirement.
Everything You Need in a REST Client
RESTK is built for professional API development. These are the core capabilities that make it the REST client developers choose over browser-based and Electron alternatives.
Request Builder
Build requests with full control over headers, query parameters, and body content. Supports JSON, form-data, x-www-form-urlencoded, raw text, binary file uploads, and GraphQL queries with variable support.
Environment Variables
Create multiple environments for development, staging, and production. Manage variables, dynamic values, and secrets. All secrets are encrypted locally with AES-256 using keys from your OS keychain.
Response Inspector
Inspect responses with pretty-printed JSON and XML formatting, syntax highlighting, header and cookie viewers, and a detailed timing breakdown showing DNS, TLS, connect, TTFB, and download phases.
Authentication
Built-in support for OAuth 2.0 (all grant types), Bearer tokens, Basic Auth, API Key, JWT generation, NTLM, Digest Auth, and AWS Signature v4. Tokens are stored in your OS keychain, not in plain text.
Code Generation
Generate code snippets from any request in 15+ languages including cURL, Python, JavaScript, TypeScript, Go, Rust, Java, C#, PHP, Ruby, Swift, and Kotlin. Copy and paste directly into your codebase.
Request History
Every request you send is stored locally with the full request and response data. Search by URL, method, status code, or date. Filter, compare, and replay past requests without any cloud dependency.
A Request Builder Built for Professionals
The RESTK request builder gives you complete control over every aspect of your HTTP requests. No compromises, no hidden limitations, no features locked behind a paywall.
Building API requests should feel natural and efficient. RESTK provides a purpose-built interface where every component of an HTTP request is accessible without navigating through nested menus or modal dialogs. Headers, query parameters, body content, authentication, and scripts are organized into clear tabs that you can switch between instantly.
The JSON body editor includes syntax highlighting, automatic formatting, bracket matching, and inline validation. If your JSON is malformed, you see the error before you send the request, not after. For form-data requests, you can attach multiple files, set content types per field, and preview the multipart payload before sending.
Configure unlimited headers with autocomplete for common header names and values
Add query parameters with URL encoding handled automatically
Compose JSON bodies with syntax highlighting, formatting, and schema validation
Upload files via form-data with multi-file support and progress indicators
Send GraphQL queries with variable binding and introspection support
Attach pre-request scripts to modify headers, generate tokens, or set variables dynamically
Attach post-response scripts to run assertions, extract values, and chain requests
Set per-request timeouts, follow redirects, and configure TLS certificate options
Why a Native REST Client Matters
Most REST clients are Electron apps — web browsers disguised as desktop applications. RESTK is a true native application built with SwiftUI on macOS and native APIs on Windows. The difference is measurable.
Startup Time
RESTK launches instantly because it is a compiled native binary. Electron-based clients must boot Chromium and load web assets before they become responsive.
RESTK (Native)
Under 1 second
Electron-Based Clients
3 to 8 seconds
Memory Usage
Native UI frameworks use a fraction of the memory that a full Chromium instance requires. This means more headroom for the rest of your development environment.
RESTK (Native)
Under 100 MB
Electron-Based Clients
500 MB to 1 GB+
CPU Usage at Idle
When RESTK is sitting in the background, it consumes virtually no CPU. Electron apps continue running renderer processes and garbage collection cycles even when idle.
RESTK (Native)
Near zero
Electron-Based Clients
2 to 5% constant
When you make hundreds of API requests per day, the cumulative time saved with a native client is significant. Faster startup, smoother scrolling, and lower resource usage mean your REST client stays out of the way and lets you focus on your APIs.
Frequently Asked Questions
Common questions about using RESTK as your REST API client.
What is a REST client?
A REST client is a tool that lets you send HTTP requests to RESTful APIs and inspect the responses. Developers use REST clients to test API endpoints, debug integrations, explore third-party APIs, and validate that their backend services work correctly before writing frontend code. A good REST client provides a visual request builder, environment variable management, authentication helpers, and response inspection tools so you can work with APIs efficiently without writing throwaway code or using raw cURL commands.
How is RESTK different from Postman?
RESTK is a native desktop application built with SwiftUI on macOS and native APIs on Windows. Postman is an Electron app that wraps a Chromium browser. This architectural difference means RESTK starts faster, uses less memory, and runs without internet access. RESTK stores all data locally by default with AES-256 encryption, while Postman requires cloud accounts and syncs data to their servers. RESTK also includes local MCP integration for AI-powered workflows, a modern Nova scripting engine, and pricing that is 36% lower than Postman Pro. For a detailed comparison, see our full RESTK vs Postman breakdown.
Does RESTK support GraphQL?
Yes. RESTK includes a dedicated GraphQL editor with syntax highlighting, schema introspection, query variable support, and response formatting. You can send GraphQL queries and mutations just like REST requests, with full support for authentication, environment variables, and pre-request scripts. The GraphQL editor auto-discovers your schema if the endpoint supports introspection, providing autocomplete for fields and types. You can also import GraphQL collections and generate code snippets for GraphQL requests in multiple languages.
Can I import from other REST clients?
Yes. RESTK supports importing collections and environments from Postman (v2.0 and v2.1 formats), Insomnia, OpenAPI/Swagger specifications, HAR files, and raw cURL commands. The import process preserves your folder structure, request configurations, headers, body content, authentication settings, and environment variables. Most developers complete their migration in under five minutes. For step-by-step instructions, see our import documentation.
Is RESTK free to use?
Yes. RESTK offers a generous free tier that includes unlimited requests, unlimited collections, local storage, environment variables, request history, code generation, and import/export functionality. The free tier is not a time-limited trial. It is a permanent plan that covers the needs of most individual developers. Pro features such as advanced Nova scripting, team collaboration with encrypted sync, priority support, and extended MCP capabilities are available at $9 per month.
Learn More About REST API Testing
Explore guides, comparisons, and best practices for working with REST APIs.
How to Test REST APIs
A practical guide to testing RESTful APIs, from basic GET requests to complex authentication flows and automated test suites.
Read articleREST API Testing Best Practices
Learn the best practices for structuring your API tests, managing environments, and maintaining reliable test suites.
Read articleGraphQL vs REST API Testing
Understand the differences between testing GraphQL and REST APIs, and how RESTK handles both protocols in a single tool.
Read articleOffline API Testing
Discover how RESTK works fully offline, with local storage, no forced cloud sync, and support for air-gapped environments.
Learn moreReady to try a better REST client?
Download RESTK and experience a native, offline-first REST client that keeps your data private and your workflow fast. Free to start, no account required.