HTTP Headers Inspector

About

HTTP Headers Inspector is a lightweight developer tool that shows HTTP request and response headers for every network request made by the current tab.
Status Code on the Icon
The extension icon dynamically changes to display the HTTP status code of the current page — 200, 301, 404, 500 and so on — with color coding so you can see the status at a glance without opening any panel.

Green — 2xx (Success)
Orange — 3xx (Redirect)
Red — 4xx (Client Error)
Purple — 5xx (Server Error)

Redirect Chain Tracking
Easily see the full redirect path from the original URL to the final destination. Each step in the chain shows the status code, Location header and full response headers. Perfect for debugging 301/302 redirects across domains.
Request & Response Headers
Expand any request to view both request and response headers. Headers are color-coded by category:

Blue — Standard headers
Green — Security headers (HSTS, CSP, X-Frame-Options, CORS)
Orange — Cache headers (Cache-Control, ETag, Expires)
Pink — Custom headers (X-, CF-)

POST Body Inspection
View the contents of POST, PUT, and PATCH requests:

Form data displayed as key=value pairs
JSON payloads automatically formatted with indentation
File upload indicators

Filter & Search

Filter requests by type: Document, XHR, JS, CSS, Image, Font
Search across URLs and header names/values
Real-time counters for each category

Export & Copy

Copy All Headers — copies all filtered headers as plain text
Export HTML — generates a beautiful standalone HTML report with the same dark theme, ready to share or archive

Privacy First

No external connections — all styles and fonts are built-in
No data collection — everything stays in your browser
No tracking — zero analytics or telemetry
Works completely offline after installation

Technical Details

Manifest V3 compatible
Minimal memory footprint — stores up to 200 requests per tab
Automatically clears data on navigation
Keyboard shortcut: Ctrl+F to focus search

Perfect for web developers, QA engineers, SEO specialists and anyone who needs to quickly inspect HTTP headers, debug redirects or verify security headers.