Requestly icon

Requestly

An open-source HTTP interceptor for redirecting URLs, modifying headers and mocking requests.

Reviewed by Xplorekit's independent developer · Last checked · How we choose

Add to Chrome Open source · Chrome Web Store · Source on GitHub

Why it's a strong pick

Requestly lets you change what a page sends and receives, so you can test without touching the server. It is open source under AGPLv3, and its code is public on GitHub. The license file shows BrowserStack Inc. as the copyright holder. It uses Manifest V3, Chrome's current extension format. The repository's latest release commit is dated 29 September 2026. That is a commit date, not a store date.

What it does

The package describes it as a browser extension acting as a web debugging proxy to intercept and modify HTTP and HTTPS requests. You write rules, then Requestly applies them as you browse. The README says it can import settings from Charles Proxy, ModHeader and Resource Override in one click.

Key features

  • Intercept and modify. Change HTTP and HTTPS requests and responses.
  • Mocking. Return test responses instead of the real ones.
  • Imports. Bring in rules from Charles Proxy, ModHeader and Resource Override.
  • DevTools page. The manifest adds a page inside Chrome DevTools.
  • Side panel. The manifest includes a side panel for network recording.
  • Open source. Code outside the ee folder is under AGPLv3.

Who it's for

Requestly is for front-end and QA developers who modify headers, redirect URLs or mock requests while testing. It asks for strong browser powers, so it suits people who know what the rules do. If you only want to read JSON or inspect state, a lighter tool is a better fit.

What permissions does Requestly ask for?

Its manifest asks for browsingData, contextMenus, declarativeNetRequest, proxy, scripting, sidePanel, storage, tabs, unlimitedStorage, webNavigation and webRequest. It also asks for access to all sites and runs on http and https pages in all frames. Those powers let it rewrite traffic. Read the install prompt before you add it.

Who owns Requestly?

The license file in the repository reads "Copyright (c) 2025-present BrowserStack Inc." That is the only ownership statement we read. The code is open source under AGPLv3, except anything in an ee folder, which has its own license. Check the license file if you plan to reuse the code.

Should I leave it switched on all the time?

We suggest not. The research behind this page found broad powers, and that is a practical tip, not a claim from the developer. Turn rules on when you are debugging and review each rule before you enable it. Switch them off when you finish.

What does it do with my data?

We could not read the developer's privacy policy when we checked; read it before installing. The README links to a security and privacy page on the developer's docs site, which we did not open. The manifest shows broad access to all sites.

FAQ

Is it open source? Yes, under AGPLv3, with an exception for the ee folder.

Does it use Manifest V3? Yes. The README says it is based on Chrome Manifest V3.

Can I bring rules from ModHeader? Yes. The README lists one-click imports from ModHeader, Charles Proxy and Resource Override.

Good to know

Start with one simple rule, such as a header change on a test site, and check the result in DevTools. Keep rules named clearly so you know what is active. Remove rules you no longer use, because they apply to the pages you browse.

Other developer tools to compare

Requestly is one of 13 picks in our developer tools guide:

  • Redux DevTools: Inspect actions and state in Redux apps, with time-travel debugging and action replay. Open source.
  • Apollo Client Devtools: Inspect queries, mutations and the cache in Apollo Client apps, and run queries in the Explorer. Open source.
  • Preact Developer Tools: Browse the component tree, props and state of Preact apps. Open source.
  • Lighthouse: Run performance and quality audits on the current page from a popup. Open source.
  • JSON Formatter: Turn raw JSON pages into a readable tree. Open source.
  • React Developer Tools: Inspect React components, props and state in a Chrome DevTools panel. Open source, by Meta.
  • Vue.js devtools: Debug Vue 3 apps in a DevTools panel. Vue 2 apps need the older v6 extension. Open source.
  • Solid DevTools: debug SolidJS reactivity.
  • Ember Inspector: inspect Ember.js apps.
  • MobX Developer Tools: debug MobX apps.
  • Refined GitHub: Simplifies GitHub and adds 100+ small improvements for repos and pull requests. Works on GitHub.com only. Open source.
  • Header Editor: Rewrites request and response headers, redirects and blocks requests with rules you set. The Chrome build is the Lite version. Open source.

This is a third-party extension, not built or maintained by Xplorekit. We link to the official Chrome Web Store listing — install and permissions are entirely between you and the extension's own publisher.