Message & HTTP Header Analyzer

Parse raw HTTP response headers or RFC 5322 email headers — paste only, no network lookups.

100% In-Browser & Private — your data never leaves this device
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How to use the Header Analyzer

  1. Paste raw headers (HTTP status block or email headers).
  2. Choose Auto-detect, HTTP, or Email format.
  3. Review highlighted fields and the full header list.

FAQ

Can this fetch headers from a URL?
No — PeachTools only parses what you paste for privacy. Use browser DevTools to capture headers first.

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