Clearheader – Modify HTTP Headers

Add, change and remove HTTP request and response headers. Profiles, URL filters and a URL tester. No account, no ads, no tracking.

Clearheader adds, changes and removes the HTTP headers your browser sends and receives. Set an Authorization token for a staging API, test CORS, switch the User-Agent, add feature-flag headers, or remove a Content-Security-Policy while you debug. No account, no ads, no tracking. Clearheader only works on the sites you allow, keeps everything on your computer, and makes no network requests of its own. HEADER RULES • Request and response headers: set, remove, or append (where the browser allows appending) • Several profiles at once, each with its own short title and colour on the toolbar badge • Switch everything, one profile or a single row on and off, and add a comment to any row • Quick start: one click adds a Bearer token, CORS headers, a mobile User-Agent, X-Forwarded-For or no-cache, or removes Content-Security-Policy FILTERS • Limit a profile to domains (example.com and its subdomains), wildcard patterns or regular expressions • Exclude URLs, pick request types, or limit a profile to requests made by certain sites or to one tab SEE WHAT'S HAPPENING • The toolbar badge shows whether your profiles apply to the page you're on • When nothing applies, the popup says why (the profile is off, its rows are off, or its filters don't match), and when a switch is the reason, turns it back on in one click • The URL tester: type any address to see every header change the browser will make, and why each profile applies or not MOVING FROM MODHEADER? Paste a ModHeader export or choose the file. You see exactly what will be added, and what can't come over, before anything changes. Several profiles imported at once start switched off, so nothing changes until you choose. Clearheader also exports and imports its own profiles, as a file or through the clipboard. PRIVACY AND PERMISSIONS • No access to any site at install. Allow a site (with its subdomains) when a profile needs it, or all sites in one click. The browser asks every time, and you can remove access in Options → Site access. • Your profiles stay in your browser's storage on this computer: no account, no sync, no server. • Clearheader never sees your requests. The browser applies the rules itself, through its declarativeNetRequest API. • On sites you've allowed, Clearheader reads your open tabs' addresses to show the badge. They're checked on your computer and never stored or sent. • Every permission is explained in plain words on the first page you see after installing. GOOD TO KNOW • If a web app on one site calls an API on another site, allow both: the browser needs access to the page making the request too. • Pause and resume all header changes with Alt+Shift+H (you can change the shortcut). • Use the popup for quick changes, or the full editor in its own tab. • Light and dark mode, following your browser. • Works in Google Chrome and Microsoft Edge. • Free. Header rules and profiles will never be behind a payment. NOT YET • URL redirects and cookie editing • Firefox Questions or problems: pocketutility.labs@gmail.com ModHeader is a trademark of its owner. Clearheader is not affiliated with or endorsed by ModHeader.