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 up to 3 pages, 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. Need more scans? Script Sentinel Premium adds monitored scans up to 10 pages, scheduled drift checks, report-only rollout guidance, and safe enforcement support.
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:
- Crawling the DOM: We use a headless browser to execute JavaScript, ensuring dynamic resource loading is detected.
- Identifying Mixed Content: The scanner flags HTTP resources loaded on HTTPS pages, which are blocked by modern browsers.
- 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.