Mixed Content Checker
A mixed content checker audits HTTPS web pages to locate insecure resources loaded over unencrypted HTTP connections. Loading HTTP images, scripts, stylesheets, or iframes on an HTTPS page triggers browser security warnings, breaks green padlock indicators, and introduces man-in-the-middle security vulnerabilities.
Evaluated 100% locally via DOMParser. Unencrypted assets are flagged by tag and risk category.
The HTML source is retrieved securely via SafeUrlService and analyzed in your browser.
| # | Severity | Element | Insecure HTTP Resource URL | Remediation Recommendation |
|---|
What is a mixed content checker and when should you use it?
When a website migrates to SSL/TLS encryption, every asset on the page—including JavaScript bundles, CSS stylesheets, web fonts, images, and embedded iframes—must be delivered exclusively over HTTPS. If any resource requests an unencrypted `http://` address, browsers classify the page as containing mixed content. Modern browsers automatically block active mixed content (scripts and stylesheets), causing broken layouts or failed functionality. Passive mixed content (such as images) displays security warnings in the address bar. Use this tool to inspect pasted HTML source code or scan a live HTTPS URL via our secure probe. To audit broader server transport security, use our HTTP Security Headers Checker and HTTP to HTTPS Redirect Checker.
How do you use it?
- Select either Paste HTML Source (for 100% private in-browser analysis) or Fetch Live HTTPS URL.
- Provide your HTML markup or enter the HTTPS page address.
- Click the Scan for Mixed Content button to execute the security audit.
- Review the summary breakdown separating high-risk active content from passive image warnings.
- Update hardcoded http:// asset paths in your CMS templates or database to use relative or https:// URLs.
Working on a comprehensive technical audit? Browse all free SEO tools to discover the next step in your workflow, or contact our technical support team if you require a specialized custom utility.
Result interpretation & practical applications
When evaluating the output of the mixed content checker, review the parsed metrics against your specific site architecture. Outputs are formatted for direct implementation into your HTML source, web server configuration, or Google Search Console audit files.
Always inspect generated values for contextual nuance. Automated tools highlight structural patterns, but manual verification confirms that technical directives align with your overarching SEO strategy.
Technical rules and limitations
- Active mixed content encompasses `