Professional HTTP header editor for Chrome and Firefox โ free forever
Add the extension to Chrome and click the icon in your toolbar. You'll see a professional dark interface with profile circles on the left.
Click the "+" circle to create different header configurations. Each profile can have unlimited request and response headers.
Use the "Add header" buttons to create custom HTTP headers. Each header has a checkbox to enable/disable individually.
Headers are applied in real-time! Switch profiles by clicking numbered circles. Use the pause button to temporarily disable.
Add Authorization: Bearer token123 for testing authenticated endpoints
Add Access-Control-Allow-Origin: * to test cross-origin requests
Set X-Environment: staging to test against different backends
Change User-Agent to test mobile vs desktop responses
No subscriptions, no premium tiers, no feature limitations. Everything is completely free, unlike competitors charging $5-15/month.
Create as many header configurations as you need. Most free alternatives limit you to just 3 profiles.
English, ็ฎไฝไธญๆ, ็น้ซไธญๆ, ๆฅๆฌ่ช, ํ๊ตญ์ด, ะ ัััะบะธะน and Espaรฑol โ switch from the toolbar, or let it follow your browser.
Modify request and response headers instantly using Chrome's latest declarativeNetRequest API. No page refreshes needed!
Toggle any header between set and append mode โ perfect for multi-value headers like Accept, Cookie or Accept-Encoding.
Scope a profile to specific domains, or to a Chrome tab group โ keep sandbox headers in their tabs and never mix environments again.
Beautiful dark theme with numbered profile circles, checkboxes for individual headers, and intuitive controls.
Temporarily disable all headers without losing your configurations. Perfect for quick testing comparisons.
Back up or share your profiles as a JSON file with one click, and import configurations โ including profiles exported from ModHeader.
Zero data collection, zero tracking. All configurations stored locally on your device only.
This extension costs nothing, and no one pays me to maintain it or to build new things into it. It gets better in my own time.
Want something improved? Open an issue and let's talk it through โ that's free too, and it's the best way in. Open an issue โ
Chip in and your request moves up my queue. And if you'd rather not, no hard feelings โ nobody ever turned down a glass of water ;)
Either way, it stays free for everyone.
We don't collect, track, or store any personal information. No analytics, no telemetry, no user data.
All your header configurations stay on your device using Chrome's secure local storage.
Full transparency - inspect the code on GitHub to verify our privacy claims.
Made with โค๏ธ for the developer community