HeaderLoom

Add, change and remove HTTP request headers for API testing and debugging. Works only on your machine.

HeaderLoom adds, changes and removes HTTP request headers on the sites you choose. It is built for developers and QA testers who need to send an auth token, an environment flag or a trace ID without changing their app. What you can do • Set a header to a value, append to list headers such as Accept-Language, or remove a header completely. • Turn single rules on and off, or pause everything in one click from the toolbar. • See straight away when Chrome would reject a header, with the reason. • Import the request headers from a ModHeader export file. Private by design • Works only on your machine. Rules are kept in Chrome's local storage and are never synced or sent anywhere. • No account, no analytics, no ads and no remote code. • No access to all websites at install. Chrome asks you to confirm each site when you add it, and you can remove it at any time. • Changes are made by Chrome's own declarativeNetRequest rule engine, so the extension never reads your pages or your traffic. Free All of the above is free, with no limit on the number of request rules. An optional one-time Pro unlock for multiple profiles and response rules is planned; it is not on sale yet. Support is by email only, on a best-effort basis: support@headerloom.com Privacy policy: https://headerloom.com/privacy