ModHeader – Modify HTTP Headers

Add, change or remove HTTP request & response headers per site. Fix CORS, set user agent, send auth tokens, redirect URLs.

Add CORS headers, change the user agent, send auth tokens, remove CSP and redirect URLs, per site, while you develop and test. ★ MOVE YOUR PROFILES IN ONE STEP Export your profiles from ModHeader (profile menu → Export), then paste the JSON or drop the file into HeaderSwap. Request headers, response headers, URL filters and redirects are converted for you. Several profiles at once are fine. ★ SAFE BY DESIGN - No ads, no injected scripts, no remote code. Everything HeaderSwap runs ships inside the extension - Built on Chrome's declarativeNetRequest API (Manifest V3): HeaderSwap changes headers but cannot read your pages or traffic - Site access is requested only when you need it, and can be limited to the domains you choose - Your headers and URLs stay on your device. Share links carry the profile inside the link itself, not on our server. Profiles are uploaded only if you turn on Premium sync - Anonymous usage stats (which features are used, never URLs or header values) can be turned off at any time ★ WHAT YOU CAN DO - Add, change or remove any request header: Authorization, Cookie, User-Agent, Referer, X-Forwarded-For or your own X- headers - Modify response headers: add Access-Control-Allow-Origin to fix CORS errors, remove Content-Security-Policy or X-Frame-Options - Set, Append or Remove each header - Apply to all sites, or only to the domains, URL patterns or regex you choose, and exclude the rest - Redirect URLs, with regex and capture groups (for example, send API calls to localhost) - Profiles for each project or environment (dev, staging, prod), switch in one click - One-click presets: Allow CORS, Disable cache, Mobile user agent, Remove CSP, Bearer token - Share a profile with a teammate by link, with an option to hide tokens and cookies - Pause everything with one switch. The badge shows how many headers are active ★ HOW TO USE - Click the HeaderSwap icon. - Type a header name and value, or pick a preset. - Click "Allow access" if asked, then reload the page. ★ FREE - Unlimited request and response headers - Domain, URL and regex filters - 2 redirects per profile - Up to 3 profiles - Presets, import, export and share links ★ PREMIUM - $4/month or $40/year - Unlimited profiles - Unlimited redirects - Apply a profile to the current tab only - Sync profiles across your computers Sign in with Google to buy or manage Premium. Cancel anytime. Made for web developers, QA testers, API developers and security testers. Questions or ideas: support@getpickads.com Privacy: https://getpickads.com/headerswap/privacy