W3C Permissions-Policy (Feature-Policy) Header Builder
Enforce least-privilege browser hardware controls: disable camera, microphone, GPS, and WebUSB.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. No data is ever transmitted across the network.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
How to Use W3C Permissions-Policy (Feature-Policy) Header Builder
Toggle permissions for camera, microphone, geolocation, and payment APIs.
Choose Block (), Self (self), or All (*).
Copy the HTTP header string or Next.js/Nginx snippets.
Frequently Asked Questions
What is Permissions-Policy?
Permissions-Policy is the modern W3C standard replacing Feature-Policy to control browser API access in documents and iframes.
How do I block all third-party iframes from accessing the microphone?
Set microphone=(self) or microphone=() in your response header.
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