HeaderX
Developer Tools
Free
HeaderX injects custom HTTP request headers into your Safari browsing session — the essential companion for web developers, API testers, and QA engineers.
Point HeaderX at your development environment, define your headers once, and flip them on whenever you need them. No proxy setup, no configuration files, no leaving the browser.
DEFINE HEADERS AS JSON
Describe your headers in a simple JSON editor — paste an entire set at once:
{"X-Debug-Mode": "enabled", "Authorization": "Bearer dev-token"}
Or use the array format to keep headers saved but individually switched off.
TWO VIEWS, ONE TOGGLE
Edit as raw JSON or flip to List view, where every header gets its own checkbox. The master toggle in the corner turns everything on or off instantly — your configuration stays saved either way.
REUSABLE PROFILES
Save named header sets — one per project, environment, or test scenario — and switch between them in two clicks.
FEATURES
• One-tap master toggle
• JSON editor and checkbox list views
• Per-header enable/disable
• Named profiles for quick switching
• Settings persist across browser restarts
• Works in Private Browsing (optional)
GOOD TO KNOW
Standard header names (Authorization, Accept-Language, User-Agent, and other HTTP-spec headers) are applied to all requests through Safari's native rule engine. Custom header names (X-My-Header and similar) are applied to fetch and XHR requests made by web pages — a Safari platform constraint on custom names in network rules. For typical API-debugging workflows, this covers exactly the requests you care about.
Headers apply to every site while the toggle is on — remember to switch off when you're done testing, especially with authentication headers.
PRIVACY FIRST
Everything stays on your device. HeaderX collects no data, phones home to no one, and contains no analytics. What you configure is nobody's business but yours.
Ratings & Reviews
- This app has not received enough ratings or reviews to display an overview.
Toolbar status at a glance
Extension icon shows a green badge with the number of active headers when HeaderX is on
Icon switches to an active (green) state when enabled; clears when off
Smarter profiles
Profiles use a single searchable field — type to find or create a profile name
Selecting a saved profile loads its headers and applies them automatically (no Load button)
Apply updates live header injection; Save (icon) persists the current headers to the profile
Compact save and delete icon buttons next to the profile field
Warning before switching profiles if you have unsaved edits
Confirmation before deleting a profile
Header editing
Edit individual headers inline in List view (toggle, edit name/value, save or cancel)
Safari-specific
Toolbar badge still updates when rules apply, even if profile storage write fails intermittently
Non-standard headers still fall back to in-page injection for fetch/XHR when Safari rejects them via network rules
The developer, Gyuman Kim, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Provider
- Gyuman Kim
- Size
- 1.3 MB
- Category
- Developer Tools
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPad
Requires iPadOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 10.14 or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Chester Kim