Header Override: An Open-Source ModHeader Alternative for HTTP Headers and Cookies

Header Override — Fri, 24 Jul 2026 09:06:38 +0000

Header Override: An Open-Source ModHeader Alternative for HTTP Headers and Cookies

If you are looking for a ModHeader alternative, Header Override provides a simple and focused way to modify HTTP headers and cookies directly in your browser.

Header Override is an open-source browser extension for Chrome, Microsoft Edge, and Firefox. It lets you create local rules for request headers, response headers, request cookies, and response cookies without changing your application code.

Why use Header Override?

The workflow is simple:

Create a header or cookie rule.
Choose the URL pattern where it should apply.
Enable the rule and test the result in your browser.

You can modify debug headers, feature flags, user identifiers, authentication settings, and cookies for selected requests.

URL-based rules

Each rule can be scoped to specific URLs using browser-supported URL filter patterns. This keeps changes limited to the requests where they are needed and helps avoid affecting unrelated websites or environments.

Local profiles

You can create separate profiles for development, staging, testing, client accounts, or different API configurations.

Profiles can be switched from the extension popup and imported or exported as JSON files.

Browser support

Header Override works in Google Chrome, Microsoft Edge, and Mozilla Firefox.

Install Header Override

Header Override is a lightweight ModHeader alternative for local HTTP header and cookie overrides, URL-scoped testing, and reusable browser profiles.

Learn more at headeroverride.com.

View the source code on GitHub.

Header Override: An Open-Source Browser Extension to Modify HTTP Headers and Cookies

Header Override — Fri, 24 Jul 2026 08:45:15 +0000

Header Override: An Open-Source Browser Extension to Modify HTTP Headers and Cookies

Header Override is an open-source browser extension that lets you modify HTTP request headers, response headers, request cookies, and response cookies directly in the browser.

It provides a simple way to test websites, APIs, staging environments, authentication flows, and feature flags without changing application code or backend configuration.

What can you do with Header Override?

Create local rules that apply only to selected URLs. You can add or replace HTTP headers, override request cookies, modify response cookies, and control cookie attributes such as Domain, Path, SameSite, Max-Age, and Secure.

Rules can be enabled, disabled, deleted, and documented with comments. URL filters help keep each change limited to the requests where it is needed.

Local profiles for different environments

Header Override supports up to five local profiles. You can use separate profiles for development, staging, testing, client accounts, or different API configurations.

Profiles can also be imported and exported as JSON files, making it easier to move configurations between browsers or computers.

Privacy-focused by design

All rules are stored locally in browser extension storage. Header Override does not require an account and does not use analytics, advertising, tracking, remote code, external servers, or third-party data sharing.

Browser support

Header Override is available for Chrome, Microsoft Edge, and Firefox.

Install Header Override

If you need a lightweight, open-source alternative to larger HTTP header modifier tools, Header Override focuses on the core workflow: create a rule, choose a URL, and test the result.

Learn more at headeroverride.com.

View the source code on GitHub.

DEV Community: Header Override

Header Override: An Open-Source ModHeader Alternative for HTTP Headers and Cookies