Loading
Build Content Security Policy headers.
The CSP Header Builder & Validator is a web application security utility designed to construct, evaluate, and test Content-Security-Policy (CSP Level 3) response headers. By defining granular directives for scripts, styles, images, iframes, and connect endpoints, it helps developers prevent cross-site scripting (XSS), clickjacking, and unauthorized data exfiltration.
CSP is an HTTP response header that instructs modern web browsers which resources (scripts, images, stylesheets) are permitted to load and execute, mitigating XSS attacks.
Allowing "unsafe-inline" lets attackers execute injected inline scripts via reflected or stored XSS vulnerabilities. Use cryptographic nonces or hashes instead.
CSP controls which origins a browser page can load resources from. CORS (Cross-Origin Resource Sharing) governs whether an external origin can read resources from your server API.
Yes. You can use the "Content-Security-Policy-Report-Only" header to monitor violations sent to a reporting endpoint without blocking resource execution.
Help us enhance VelnoxLabs developer utility standards. Share your feedback below!