HTTP response headers explainer
Paste raw response headers from curl -I or browser devtools. Tolerates the HTTP/1.1 200 status line. Your data never leaves the browser.
Response headers
Privacy: Headers are parsed locally. For Cache-Control tuning use the cache builder; for CSP use the CSP generator.
Parsed headers
| Header | Category | Value | Explanation |
|---|---|---|---|
Findings
About this tool
Response headers tell browsers and CDNs how to cache, secure, and interpret your content. Paste the raw block from curl -I or the Network tab — status line included. Parsing happens locally; nothing is uploaded.
The explainer covers roughly 60 common headers across caching, security, CORS, cookies, and content type. It flags missing security headers, info leaks like Server and X-Powered-By, and deprecated directives. Use the dedicated cache-control and CSP tools when you need to build new values, not just read existing ones.
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