Requestly is an Open-source alternative to ModHeader

Requestly is a powerful tool that goes beyond just modifying headers.
Create Rules to modify HTTP Requests.
100% ad-free. No spam ever.

Trusted by developers at


Requestly is way better than ModHeader

Requestly offers a broad range of features. It allows you to redirect requests, modify headers, query params, and response body, simulate custom responses, delay requests, and more.

No Ads

100% ad-free experience in all plans. No content is touched. No spam ever.

Open Source

Requestly is built by open source enthusiasts. Built in public.

Team Collaboration

Setup multiple workspaces for work and invite your teammates to collaborate.


Available as extension for Chrome, Firefox, Edge and desktop app for Safari, Windows & Linux, and SDK for Android & iOS


The whole Requestly extension size is <650kb and contains logic only. UI is served over web only.

Performance Optimized

Doesn’t slow down your browsing experience. Requestly won’t drain your system’s energy and memory.

Pre-made Templates

Ready to use Rules for popular use cases(Bypass CORS, Remove CSP headers), simply enable the template for you and start using.

Privacy & Security

Requestly extension processes all your requests locally on your device.Trusted by over 200,000+ developers and 5,000+ companies.

Community Support

Requestly has pretty active communities and support. It provides a more extensive support network for a broader range of issues.

For the developers, by the developers ❤️

From Debug to Deploy: Developers Trust Requestly