Headerly is a powerful and reliable browser extension designed for managing HTTP request and response headers. It allows developers and users to quickly set, append, or remove headers and easily customize web traffic.
As an open-source project, Headerly provides a clean, user-friendly experience without injecting ads into your webpages.
- DNR API Integration: Powered by Chrome's modern Declarative Net Request (DNR) API for fast and efficient network request modifications.
- Intuitive UI: A clean popup interface that makes profile management straightforward.
- Profile Import & Export: Import existing configurations and export profiles for backup, sharing, or migration.
- Flexible Configuration: Support for using radio or checkbox modes within a single profile to manage different header rules, with configurable default modes.
- Rich Filtering: Apply rules conditionally based on URL matching, Regex, domains, resource types, and request methods.
- Cookie Synchronization: Sync specific cookies across different requests (requires additional cookies permission).
Your privacy is our priority. Because Headerly strictly utilizes the declarativeNetRequest API, the browser handles all network modifications internally based on predefined rules. The extension itself has no capability to intercept, read, or analyze your sensitive data, request payloads, or response bodies.
Please make sure to read the Contributing Guide before making a pull request.
This includes instructions on how to setup development environment, test extensions, and build the final product.
Detailed changes for each release are documented in the CHANGELOG.
MIT | © 2026 aiktb made with ❤️.