Header Editor — HTTP Request Header Manager

About

HeaderEditor lets you create rules to inject, modify, or remove HTTP request headers for specific URL patterns — without a proxy server or writing code. Set Authorization headers for API testing, spoof User-Agent strings for compatibility testing, add CORS headers for local development, or block tracking headers.

**Key Features:**
- Rule-based header injection using URL patterns (glob and regex)
- Inject, modify, or remove request headers
- Pre-built templates: Authorization Bearer, User-Agent presets (mobile/desktop/bot)
- Rules toggle on/off individually or all at once
- Import/export rules as JSON for team sharing
- Works with fetch, XHR, and any browser request
- No proxy setup required — works at the browser extension level

**Who is it for?**
Backend developers testing APIs that require auth headers, frontend developers working around CORS in local development, QA engineers testing responsive behavior with User-Agent spoofing, and security researchers studying header-based access control.

**Privacy & Trust:**
All rules are stored locally in your browser. No header data, URLs, or rule configurations are sent to external servers. Anonymous analytics via Google Analytics 4 only.

Install HeaderEditor — debug faster without leaving Chrome.