HTTP Header Parser

HTTP header reader online

Review repeated headers in a pasted HTTP message. Header names become lowercase; folded continuation lines are unsupported.

How to use it

Enter the source input or select Try example. Review the displayed input. Select Run tool and inspect the result before copying or downloading.

Worked examples

Review repeated headers in a pasted HTTP message.

Worked example — HTTP Header Parser

Settings: No additional options

Input:

HTTP/1.1 200 OK
Content-Type: application/json
Set-Cookie: a=1
Set-Cookie: b=2

Output:

{
  "startLine": "HTTP/1.1 200 OK",
  "headers": {
    "content-type": [
      "application/json"
    ],
    "set-cookie": [
      "a=1",
      "b=2"
    ]
  }
}

The example returns an object with 2 top-level fields. The fields “startLine”, “headers” identify the returned values or sections.

Limitations and common mistakes

• Header names become lowercase; folded continuation lines are unsupported.

Frequently asked questions

How can I parse pasted HTTP headers and preserve repeated header values online?

Enter the source input or select Try example. Review the displayed input. Select Run tool and inspect the result before copying or downloading.

Where is my input processed?

The bundled tool processes input in your browser. It does not upload tool input to a conversion service. Other site plugins, analytics, advertising and browser extensions may have separate behavior.

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