REST API client. Send GET, POST, PUT, DELETE, PATCH requests with custom headers, body, and auth. Inspect responses with syntax highlighting.
100% browser-based — your data never leaves your device
Send HTTP requests (GET, POST, PUT, DELETE) and inspect responses from your browser.
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REST API Client is a free online api tool that send http requests (get, post, put, delete) and inspect responses from your browser. It works entirely in your browser — no downloads, no installations, and no server uploads required. backend developers, QA engineers, integration specialists use REST API Client when they need a fast, privacy-respecting way to process api data without installing additional software. It supports capabilities such as all methods, headers & body, response inspector. Additional features include history. Common use cases include test api endpoints during development without installing postman or insomnia, debug authentication flows by inspecting request and response headers, validate api responses with syntax-highlighted response bodies. All processing happens locally using modern browser APIs, which means your data never leaves your device. This makes REST API Client ideal for working with sensitive data, proprietary code, or any situation where privacy matters.
REST API Client is a free online api tool that helps you send http requests (get, post, put, delete) and inspect responses from your browser. Key capabilities include all methods, headers & body, response inspector. All processing is done locally in your browser — no data is uploaded, stored, or shared with any server. There are no sign-ups, no file size limits, and no hidden charges. It is commonly used to test api endpoints during development without installing postman or insomnia.
Type or paste the full URL of the API endpoint you want to test, including protocol (https://).
Choose the HTTP method — GET, POST, PUT, PATCH, DELETE, HEAD, or OPTIONS — based on what the endpoint expects.
Add custom headers for auth, content type, or caching. For POST/PUT, provide a JSON or form-data body.
Click Send to make the request. Review the response status code, headers, and body with syntax highlighting.
| Category | Details |
|---|---|
| Input Limits | Request timeout: Configurable (default: 30 s) |
| Response size: Browser memory bound | |
| Supported Formats | HTTP/1.1, HTTP/2, WebSocket, JSON, XML, Form data, Binary |
| Browser Engine |
|
All operations run entirely in your browser using built-in API APIs. No server uploads, no data storage, and no third-party requests.
REST API Client is ideal when you need to test api endpoints during development without installing postman or insomnia without installing software or uploading data to a server. Since everything runs in your browser, there is no setup time and no risk of your data being stored on external servers. For for collaborative API development and testing, consider using Postman. For for lightweight REST and GraphQL debugging, Insomnia may be a better fit. REST API Client fills the gap between heavyweight desktop tools and insecure online services that require uploading your data.
No. REST API Client processes everything entirely in your browser using JavaScript. Nothing you type, paste, or upload is ever transmitted to any server. Your data never leaves your device.
Yes, via a CORS proxy. Some non-CORS APIs may not work from the browser.
Request history is stored locally in your browser only.
GET, POST, PUT, PATCH, DELETE, HEAD, and OPTIONS requests.
Custom headers, JSON/form-data bodies, and query parameter builder.
View response status, headers, body with syntax highlighting.
Saved request history with the ability to replay.
REST API Client is useful in a variety of scenarios across different workflows:
Test API endpoints during development without installing Postman or Insomnia
Debug authentication flows by inspecting request and response headers
Validate API responses with syntax-highlighted response bodies
Store API base URLs and auth tokens in environment variables so you can quickly switch between dev, staging, and production.
Use the history feature to save and replay frequently used API requests for faster debugging.
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