HTTP Header Checker
Check HTTP response headers and security score for any website. Analyze HSTS, CSP, X-Frame-Options, and other security headers.
🛡️ Security Headers
📋 All Response Headers
| Header | Value |
|---|---|
HTTP Header Checker
This free HTTP header checker tool analyzes any URL's response headers and provides a security score. Check for critical security headers like HSTS, Content-Security-Policy, X-Frame-Options, and more. Get a detailed security grade and actionable recommendations.
🔥 Popular Tools
ℹ️ About HTTP Header Checker
The Http Header Checker is a free developer tool built for speed and privacy. Check HTTP response headers and security score for any website. Analyze HSTS, CSP, X-Frame-Options, and other security headers. Every operation runs entirely in your browser, which means your code, text, or payload is never uploaded to a server. Paste your input, hit the button, and get the output — formatted, validated, or transformed — in milliseconds. This Http Header Checker is designed to replace slow, bloated web apps with a single focused page that loads fast, works offline after first visit, and handles both small snippets and large inputs gracefully.
💡 Use Cases
💎 Pro Tips
- Paste your content directly — the Http Header Checker detects common input patterns and applies sensible defaults automatically.
- Use keyboard shortcuts (Ctrl/Cmd+A to select all, Ctrl/Cmd+C to copy) to speed up your workflow inside the Http Header Checker.
- For very large inputs, break them into chunks — most browser tabs can handle megabytes of text, but parsing huge payloads may freeze the UI briefly.
- The Http Header Checker does not log or store your input. If you need history, copy important outputs to a local file or note app.
- Combine the Http Header Checker with other tools on this site (formatters, converters, encoders) to build complete data pipelines without leaving your browser.
❓ Frequently Asked Questions
Yes, fully free with no signup, no API key, no watermarks, and no usage limits.
No. The Http Header Checker runs entirely client-side in your browser. Your input never touches our servers.
There is no hard limit, but expect slowdowns on inputs larger than a few megabytes, depending on your device's memory.
Yes. Outputs generated with the Http Header Checker are yours to use freely in any personal or commercial project.
Most of the logic runs in client-side JavaScript, so after the initial load you can often keep working without a network connection.
None. Because the Http Header Checker runs in your browser, you can process as many inputs as your hardware allows without API keys or throttling.