Free CSP Generator

Using the CSP Generator tool is a straightforward process designed to get you from zero to a production-ready Content Security Policy in minutes. Follow these steps for the best results:

• Step 1 — Audit Your Resource Sources: Before you begin, make a list of all external domains and services your website loads resources from. This includes CDN URLs for JavaScript libraries (e.g., cdn.jsdelivr.net), font providers (e.g., fonts.googleapis.com), analytics platforms (e.g., www.google-analytics.com), payment processors, and any APIs your frontend connects to.
• Step 2 — Configure Your Directives: In the CSP Generator interface, work through each directive one by one. For each directive, enter the trusted source URLs you identified in Step 1. Use the available keyword options like 'self' (to allow resources from your own origin), 'none' (to block all sources for that resource type), 'unsafe-inline' (use sparingly), and 'unsafe-eval' (avoid if possible).
• Step 3 — Configure Special Directives: Pay attention to directives like frame-ancestors (controls who can embed your page), base-uri (restricts base tag manipulation), form-action (controls where forms can submit data), and upgrade-insecure-requests (automatically upgrades HTTP requests to HTTPS).
• Step 4 — Generate and Copy: Once all your directives are configured, click the Generate button. The tool will output your complete, properly formatted CSP header string. Copy this output to your clipboard.
• Step 5 — Deploy in Report-Only Mode First: Before enforcing the policy, deploy it using the Content-Security-Policy-Report-Only header instead of Content-Security-Policy. This logs violations without blocking resources, letting you catch any legitimate resources you may have missed without breaking your site.
• Step 6 — Enforce and Monitor: After verifying there are no unexpected violations, switch to the enforcement header Content-Security-Policy. Add a report-uri or report-to endpoint to continuously monitor for new violations as your application evolves.

The generated policy can be applied as an HTTP response header via your web server (Nginx, Apache, Cloudflare, etc.) or through a <meta> tag in your HTML, though the HTTP header approach is always recommended for maximum security.

A CSP Generator (Content Security Policy Generator) is a powerful web security tool that helps developers, security engineers, and webmasters create valid, well-structured Content Security Policy HTTP headers without needing to manually write complex directive syntax. Content Security Policy is a browser security mechanism that allows website owners to control which resources — such as scripts, stylesheets, images, fonts, and media — a browser is allowed to load and execute on a given page.

The CSP Generator simplifies the process by providing an intuitive interface where you can configure individual directives such as default-src, script-src, style-src, img-src, connect-src, font-src, object-src, media-src, and more. Based on your selections, it automatically generates a ready-to-use CSP header string that you can deploy directly in your server configuration, web application framework, or meta tag.

Under the hood, the tool is built around the official W3C Content Security Policy specification (currently CSP Level 3), ensuring that the policies generated are standards-compliant and compatible with all modern browsers including Chrome, Firefox, Safari, and Edge. Whether you are protecting a simple static website or a complex single-page application (SPA), the CSP Generator gives you granular control over your site's security posture with zero guesswork.

Content Security Policy is one of the most critical defenses against some of the most prevalent and damaging web attacks in existence. Without a properly configured CSP, your website is vulnerable to a range of serious threats:

• Cross-Site Scripting (XSS) Attacks: XSS is consistently ranked in the OWASP Top 10 most critical web application security risks. A well-crafted CSP can neutralize XSS attacks by preventing the browser from executing injected malicious scripts, even if an attacker successfully injects code into your page.
• Clickjacking: CSP's frame-ancestors directive prevents your site from being embedded in malicious iframes, stopping clickjacking attacks that trick users into performing unintended actions.
• Data Injection Attacks: CSP restricts which external sources can interact with your application, dramatically reducing the attack surface for data exfiltration attempts where sensitive information could be sent to attacker-controlled servers.
• Malicious Script Injection via Supply Chain Attacks: By explicitly whitelisting trusted script sources, CSP can limit the damage caused by compromised third-party dependencies or CDN resources.

Beyond direct security benefits, a strong CSP demonstrates your commitment to web security best practices, which can positively impact user trust, enterprise compliance requirements (such as PCI-DSS, HIPAA, and SOC 2), and even SEO signals related to site security. Google and other search engines increasingly favor secure, well-maintained websites. Using a CSP Generator removes the barriers to implementing this critical security layer — no more manual header writing, no more syntax errors, and no more guesswork about which directives to use.

Implementing Content Security Policy effectively requires more than just generating a header — it requires strategic thinking about your application's resource needs. Follow these best practices to maximize the security benefit of your CSP:

• Start with a strict default-src: Always begin with default-src 'none' or default-src 'self' as your baseline, then incrementally add permissions for specific resource types. A strict default forces you to be explicit about every resource type you allow, minimizing accidental over-permissioning.
• Avoid 'unsafe-inline' and 'unsafe-eval': These keywords significantly weaken your CSP. Instead, replace inline scripts with external JavaScript files loaded from trusted origins. If inline scripts are unavoidable, use nonces (e.g., 'nonce-{random}') or hashes (e.g., 'sha256-{hash}') to allow only specific, known-safe inline blocks.
• Use Nonces for Dynamic Content: For server-rendered applications that must include inline scripts, generate a fresh cryptographically random nonce for every HTTP request and include it in both your CSP header and your <script> tags. This ensures that only scripts with the correct nonce can execute.
• Restrict frame-ancestors explicitly: Set frame-ancestors 'none' if your site should never be embedded in an iframe, or restrict it to specific trusted origins. This is more reliable than the older X-Frame-Options header.
• Keep your CSP policy version-controlled: Store your CSP configuration alongside your codebase and treat changes to it with the same rigor as code changes — with code review and testing in staging environments before deploying to production.
• Test thoroughly with Report-Only mode: Use Content-Security-Policy-Report-Only in all pre-production environments and monitor violation reports carefully before promoting a policy to enforcement.
• Avoid wildcards: Using * as a source value defeats the purpose of CSP. Always use specific domain names or paths wherever possible.
• Regularly audit and update your policy: As your application evolves — new third-party integrations, new CDNs, new analytics tools — your CSP must be updated accordingly. Schedule periodic reviews to keep your policy current and minimally permissive.

Even experienced developers make critical errors when configuring Content Security Policy. Here are the most common mistakes to avoid when using the CSP Generator:

• Going straight to enforcement mode: Deploying a new or changed CSP directly in enforcement mode (Content-Security-Policy) without first testing it in report-only mode is the number one cause of accidentally broken websites. Always use Content-Security-Policy-Report-Only first, monitor violations, and only switch to enforcement after confirming all legitimate resources are whitelisted.
• Using 'unsafe-inline' as a quick fix: When a CSP blocks inline scripts and things break, developers often add 'unsafe-inline' to resolve the issue quickly. This essentially nullifies the XSS protection that CSP provides. The correct fix is to move inline scripts to external files or implement nonce-based allowances.
• Forgetting WebSocket and Fetch connections: Developers often configure script-src and style-src correctly but forget to add API endpoints, WebSocket servers, or analytics beacons to connect-src. This causes AJAX calls, fetch requests, and real-time connections to be blocked silently.
• Not including all subdomains: If your site loads resources from multiple subdomains (e.g., api.example.com, assets.example.com), failing to list them all in the appropriate directives will cause those resources to be blocked. Use *.example.com only if you trust all subdomains, or list each subdomain explicitly for tighter control.
• Ignoring the report-uri / report-to directive: Deploying a CSP without a reporting endpoint means you have no visibility into policy violations — including legitimate resources being blocked or actual attack attempts. Always configure a reporting endpoint so you can monitor your policy's effectiveness in real time.
• Applying CSP only via meta tags instead of HTTP headers: While CSP can be delivered via a <meta http-equiv> tag, this approach has limitations. Certain directives like frame-ancestors, report-uri, and sandbox are not supported in meta tags, and the policy is applied later in the page-load cycle, reducing its effectiveness. Always prefer HTTP headers.
• Treating CSP as a one-time setup: Content Security Policy is not a "set it and forget it" solution. As your application grows and integrates new third-party services, your policy must be updated accordingly. Neglecting ongoing maintenance leads to either a broken user experience (missing sources) or a dangerously loose policy (outdated over-permissive rules).