HTTP Header Formatter

Paste raw HTTP headers from DevTools, cURL or logs — get clean JSON. Or convert JSON back to header lines.

Raw headers or JSON

Duplicates

Result

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Parsing rules

Header lines are split on the first colon: the name is trimmed, the value keeps its inner spacing. Leading request lines (e.g. GET / HTTP/1.1) are ignored automatically. When the same header appears multiple times — common with Set-Cookie or Accept — it becomes a JSON array, or a comma-joined value if you prefer. Whitespace-only continuations of folded headers are joined to the previous value.

FAQ

Does it handle cURL -v output?

Lines prefixed with >, < or >> are cleaned automatically, so pasting verbose cURL output works.

Is my data uploaded?

No. Parsing runs in your browser — safe for headers containing authorization tokens.

HTTP Header Formatter — FAQ

Is HTTP Header Formatter free to use?

Yes. It is completely free, with no signup, no installation and no usage limits.

Is my data uploaded to a server?

No. The tool runs entirely in your browser — the data you paste or upload never leaves your device.

Does it work on mobile devices?

Yes. It works in any modern desktop or mobile browser, with nothing to install.