Content Security Policy Generator & Scanner

Build a secure CSP in seconds. As an advanced Content Security Policy Builder, Script Sentinel scans your live site to automatically construct a whitelist of trusted sources, removing the guesswork from manual policy creation.

A Content Security Policy (CSP) helps prevent cross-site scripting (XSS) and data injection attacks by controlling which resources can load on your website.

Our free CSP Generator scans your site, detects scripts, styles, and third-party domains, and generates a secure Content Security Policy header you can deploy immediately.

Whether you need to fix unsafe-inline errors, implement nonces, or harden your production environment, this tool simplifies the entire process.

Enter a URL and hit Scan to begin.

The Definitive Guide to Generating a Content Security Policy in 2026

Content Security Policy (CSP) has evolved from a nice-to-have header into a critical component of modern web security. However, deploying a CSP remains one of the most challenging tasks for developers. A content security policy generator removes the guesswork, ensuring your site is protected against Cross-Site Scripting (XSS) and data injection attacks without breaking functionality.

Why Manual CSP Configurations Often Fail

Manually writing a CSP is error-prone. A single missing domain in your `script-src` can break your analytics, chat widgets, or payment gateways. Conversely, being too permissive (e.g., using `unsafe-inline` or allowing `*`) renders the policy useless.

Common pitfalls include:

  • Maintenance Fatigue: SaaS tools change their CDNs frequently. A static manual policy becomes obsolete quickly, leading to console errors.
  • Syntax Errors: CSP syntax is strict. Misplacing a semicolon or quote can invalidate the entire header.
  • Blind Spots: It is difficult to manually track every third-party script loaded by marketing tags or other dependencies.

Using an automated CSP scanner allows you to crawl your site exactly as a browser sees it, capturing every resource request to build a whitelist that reflects reality. As stated in our mission to make web security accessible, automation is the only way to scale security effectively.

How to Use a CSP Scanner to Validate Policies

Validation is the second half of the equation. Once you have generated a candidate policy, you must validate it before enforcement. Our tool functions as a rigorous Content Security Policy builder and validator by:

  1. Crawling the DOM: We use a headless browser to execute JavaScript, ensuring dynamic resource loading is detected.
  2. Identifying Mixed Content: The scanner flags HTTP resources loaded on HTTPS pages, which are blocked by modern browsers.
  3. Analyzing Inline Scripts: We automatically generate SHA-256 hashes for inline scripts, allowing you to whitelist specific code blocks without opening the door to `unsafe-inline`.

Pro-Tip: strict-dynamic and Modern Browser Support

For 2026 standards, the gold standard for CSP is strict-dynamic. This directive tells the browser: "Trust any script executed by a trusted script." This significantly simplifies CSP management for modern web applications that rely heavily on script loaders or bundlers (like Webpack or Vite).

How it works: Instead of whitelisting every single CDN (e.g., `https://analytics.google.com`), you simply add a cryptographic nonce (number used once) to your root script tag. With `strict-dynamic`, the browser will automatically trust any other scripts that your root script loads. This eliminates the need to constantly update your allowlist when third-party vendors change their URLs.

Note: While our generator provides a robust baseline, complex Single Page Applications (SPAs) may require fine-tuning. If you are struggling with nonce implementation, contact our security team for specialized support.