Reqix – API Mock, Header Editor, Request Modifier, Redirect & User Scripts

Mock APIs, edit HTTP headers and bodies, redirect URLs, run user scripts and create rules from DevTools. No account required.

Reqix combines API mocking, HTTP request and response modification, a header editor, URL redirects and userscript management in one browser extension. Build and test frontend features before the backend is ready, without changing application code or configuring a system proxy. Supports Chrome and Edge 138+. API Mock, headers and request rewriting • Set JSON, XML or text response bodies, HTTP status codes, Content-Type and delays to test success, empty data, errors and loading states. • Generate dynamic responses with JavaScript using request data, or cancel matching requests. • Add, change or remove request and response headers. Edit query parameters and JSON request bodies. • Redirect API endpoints to local, test or staging environments, and replace script, stylesheet and image URLs. Body rewriting and response mocking apply to Fetch/XHR; other resources support redirect rules only. Start with a real request Open the Reqix DevTools panel, reload the page or trigger a request, then inspect the traffic and create rules from one or several requests. Review and save your changes, confirm that the rules are enabled, and repeat the request. You can also record supported Fetch/XHR traffic and turn it into editable mock rules. DevTools inspection works independently of the request-handling switch. Rules and userscript management Group rules by project or environment, check rule hits, and use global or per-site controls. Import and export rules, groups, and page scripts as local files. Run your own JavaScript or CSS on matching pages; importing .user.js files and Tampermonkey backups does not imply full compatibility with every userscript API. Page scripts require the browser's “Allow user scripts” setting. The interface supports 10 languages and light/dark themes. Local data, clear controls Rules, scripts, request debugging data, and preferences are processed and stored in your browser. Reqix needs no account and has no cloud sync or telemetry; it does not send this data to a developer backend. Request data can include URLs, headers, bodies, and credentials. Your scripts, dynamic response code, and redirects can access the network as configured. Review sensitive data before exporting. On first install, request handling is on globally; turn it off or choose per-site controls at any time. Delete saved content or uninstall to remove local data. Website: https://reqix-dev.github.io/reqix-website/en/ Support: https://github.com/reqix-dev/reqix/issues Privacy: https://reqix-dev.github.io/reqix-website/en/privacy/