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HTTP Headers Reference

Network

Searchable reference for 80+ HTTP request and response headers

Search by header name like `Cache-Control` to quickly recall its syntax and valid directive values mid-debug, or browse split by request versus response headers when you've seen something in the wild and aren't sure which category it belongs to. A less common one like `Sec-Fetch-Site` or `Vary` is exactly the kind of thing worth looking up here before writing server logic that depends on it. It covers 80+ of the most commonly used standard headers with real example values alongside each definition, based on current MDN and RFC documentation, though some highly specialized or vendor-specific headers may not be included, and newly proposed headers are worth cross-checking against the latest spec directly. Security-related headers like CSP and HSTS are covered too, though for actually building out a full CSP policy the dedicated CSP Header Builder is the better tool. It's a static reference: nothing you search is sent anywhere.

httpheadersreferencerequestresponse

How to use HTTP Headers Reference

  • 1.Search by header name (e.g. `Cache-Control`) to quickly recall its syntax and valid directive values while debugging.
  • 2.Browse by request vs response headers when you're not sure which category a header you've seen in the wild belongs to.
  • 3.Look up a less common header (like `Sec-Fetch-Site` or `Vary`) to understand what it signals before writing server logic around it.

Frequently asked questions

Is this reference exhaustive?
It covers 80+ of the most commonly used standard headers, but some highly specialized or vendor-specific headers may not be included.
Does it show real-world examples, not just definitions?
Yes, each header includes example values alongside the definition so you can see realistic usage, not just the spec description.
Is this reference kept in sync with the actual HTTP/browser specs?
It's based on current MDN and RFC documentation, but for edge-case or newly proposed headers, always cross-check the latest spec since header semantics do evolve.
Does it explain security-related headers like CSP or HSTS?
Yes, security headers are included, though for building a full CSP policy you should use the dedicated CSP Header Builder tool.

Use via API, SDK, or MCP

cURLcurl "https://api.utilix.tech/v1/tools/http-headers" \
  -H "Authorization: Bearer utx_live_..."
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