ModHead is a versatile Chrome extension designed for modifying HTTP request and response headers dynamically. It caters to web developers, API testers, and anyone involved in HTTP API interactions, offering a user-friendly interface for managing headers in real-time. Key features include the ability to add, modify, or remove headers on the fly, support for various HTTP request types, and a flexible URL pattern matching system that allows for site-specific rules.

The extension also includes a variable system for reusable header values, auto-refresh capabilities for authentication tokens, and a modern user interface built with React. With no data sent to external servers, ModHead ensures privacy and security by storing all rules locally. Its functionality makes it ideal for debugging, multi-environment testing, and handling CORS issues, making it an essential tool for developers and QA engineers.