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Developer Utility

HTTP Header Checker Tool

Inspect raw HTTP headers and identify missing security headers.

Language: HTTPUtility: InspectUtility: Validate
Parsed headers: 3
Unique headers: 3

Missing recommended security headers: 4
- content-security-policy
- strict-transport-security
- x-content-type-options
- referrer-policy

No duplicate headers detected.

What This Tool Does

Inspect raw request/response headers to catch auth, CORS, and caching misconfigurations fast.

Use it to inspect or transform input quickly, then carry validated output into code, tests, or API requests.

Common Use Cases

  • Validate security header presence.
  • Check CORS and caching directives during rollout.
  • Debug malformed Authorization or content headers.

Common Pitfalls

  • Header correctness depends on deployment layer too.
  • Proxy/header rewriting can hide origin behavior.

FAQ

  • Can this detect missing security headers?

    Yes, it highlights common security header gaps.

  • Should I test production headers here?

    Yes, production edge behavior is what matters.

  • Does this tool send data to a backend?

    Most tools process input client-side in your browser unless explicitly noted.

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