No jargon, no gatekeeping.
There is no single best proxy interceptor. There is a best one for penetration testing, for mocking APIs in Chrome, for native mobile apps, and for Smart TVs. Here is how the 10 leading tools compare.
A proxy interceptor sits between a client and a server so you can inspect and change traffic. The big difference between tools is where they sit: as a network MITM proxy with its own root certificate, as a browser extension, or inside the app as an SDK. That choice decides setup cost, which devices work, and whether you can mock bodies without a certificate.
We grouped the tools by the job most people bring to them, and we say plainly when a competitor is the better choice.
| Tool | Type | Certificate needed | Open source | Best for |
|---|---|---|---|---|
| ProxyCeptor | Chrome extension + in-app SDK + cloud | No | No (free account) | Mocking and debugging web and Smart TV front ends; team rule sharing |
| Burp Suite | Desktop MITM proxy | Yes (bundled browser pre-configured) | No (free Community edition) | Web penetration testing |
| Requestly | Browser extension + desktop app | Extension: no; desktop: yes | Yes | Rule-based redirects, header changes, mocks |
| HTTP Toolkit | Desktop MITM proxy | Yes (automated setup) | Yes | One-click interception of browsers, Android, Node, Docker |
| Charles Proxy | Desktop MITM proxy | Yes | No (paid) | Classic cross-platform debugging, throttling |
| Fiddler Everywhere | Desktop MITM proxy | Yes | No (subscription) | Windows-heavy enterprise teams |
| Proxyman | Desktop MITM proxy | Yes (automated for iOS simulator) | No (freemium) | macOS and iOS developers |
| mitmproxy | CLI / web MITM proxy | Yes | Yes | Scripting and automation in Python |
| ZAP | Desktop MITM proxy + scanner | Yes | Yes | Free security scanning |
| Postman Interceptor | Browser extension | No | No | Capturing requests and cookies into Postman |
Burp Suite from PortSwigger is the industry standard for web security testing. Its Proxy Intercept tab pauses each request so you can edit it by hand, and Repeater, Intruder and (in Professional) the scanner build a full testing workflow on top. Burp ships an embedded Chromium browser that already trusts its certificate, which removes most setup pain for web targets.
Choose it when you are hunting vulnerabilities. Skip it when you just need to mock an API response while building a feature; it is a heavy tool for that job. See ProxyCeptor vs Burp Suite.
ZAP (formerly OWASP ZAP) is the leading free and open-source alternative to Burp, with an intercepting proxy, active and passive scanners, and strong automation for CI security checks.
mitmproxy is a free, open-source interceptor with a terminal UI (mitmproxy), a web UI (mitmweb) and a headless mode (mitmdump). Its Python addon API makes it the most scriptable option on this list.
ProxyCeptor is a Chrome DevTools extension, an in-app JavaScript SDK and a cloud workspace that all share one JSON rule format. It combines Chrome's declarativeNetRequest (for redirects, blocking and headers) with a page-level fetch/XHR/sendBeacon interceptor (for mocked bodies, JSON deep merge, JavaScript transforms and delays).
What sets it apart is certificate-free interception on devices. The same rules load into a Samsung Tizen, LG webOS or Android TV web app through the SDK, which is where desktop MITM proxies struggle. It also includes a Network tab with HAR export, rrweb session replay, and cloud rule sync with local-wins conflict handling.
Choose it when you build or test web or TV front ends and want mocks, errors and delays in seconds, shared across the team.
Requestly is an open-source browser extension and desktop app for redirect, header-modification and mock rules, and it has grown into an API client. It is a strong, well-known choice for web-only rule-based interception. See ProxyCeptor vs Requestly.
Postman Interceptor is a companion extension that captures browser requests and cookies into Postman so you can replay them as API requests. It is a capture tool rather than a modification tool. See ProxyCeptor vs Postman Interceptor.
Proxyman is a polished native macOS debugging proxy with automated certificate setup for iOS simulators and devices, breakpoints, scripting and map-local mocks. It is the default for many Apple developers. See ProxyCeptor vs Proxyman.
HTTP Toolkit is an open-source, cross-platform debugging proxy known for one-click interception of browsers, Android devices, Node.js processes and Docker containers, with mocking and rewriting rules. See ProxyCeptor vs HTTP Toolkit.
Charles is the long-standing cross-platform desktop proxy with breakpoints, map-local, rewrite rules and bandwidth throttling. It is reliable and well documented, but setup (system proxy plus root certificate on every device) is manual. See Charles Proxy alternatives.
Fiddler Everywhere from Progress Telerik is the cross-platform successor to Windows-only Fiddler Classic, aimed at teams that want a supported commercial desktop proxy. See ProxyCeptor vs Fiddler.
For security work, Burp Suite. For general HTTP debugging, Charles, Fiddler, Proxyman and HTTP Toolkit are the most widely used desktop tools. Browser-based interceptors such as ProxyCeptor and Requestly are the fastest way to mock APIs while developing.
Yes. mitmproxy, ZAP and HTTP Toolkit are open source, Burp Suite has a free Community edition, and ProxyCeptor has a free account.
Browser-extension and in-app interceptors such as ProxyCeptor, because they hook requests before encryption. Burp also avoids manual setup by bundling a pre-configured browser, but only for that browser.
Grab coffee. This goes deep.
Code interceptors belong to your app. Proxy interceptors belong to your debugging session. Mixing them up is how mock data ends up in production.
Grab coffee. This goes deep.
Every project has a hidden API nobody remembers writing, and on a TV you cannot even see it. What actually works when the device will not trust your proxy.
Create a free ProxyCeptor account to mock, delay, block and rewrite API traffic, then share the same rules with your team.