HTTP Structured Fields Workbench
Parse and canonically serialize RFC9651 Items, Lists and Dictionaries with typed values.
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How to use HTTP Structured Fields Workbench
Parse and canonically serialize RFC9651 Items, Lists and Dictionaries with typed values. Inspect strings versus tokens, dates versus integers, byte sequences, display strings, inner lists and ordered parameters without interpreting a header-specific policy.
- Provide structured field value.
- Choose the supported mode and run the tool. Review its assumptions and any reported errors.
- Copy the result or download a separate output; reset to clear the current form.
Good to know
- 64KiB ASCII,1024 top-level members,256 inner items/parameters,10000 values. Unicode uses RFC9651 percent-encoded display strings.
- Duplicate dictionary/parameter keys use the final value at their initial position. Decimal values retain exact normalized decimal text; no floating-point rounding is introduced.
- This validates generic field syntax, not a particular HTTP field definition or RFC8941-only field policy.
- Inputs are processed on this device and are not automatically saved or uploaded.
Common questions
Can every HTTP header use this grammar?
No. A header definition must explicitly specify its structured type and any further semantic constraints.
Does this change my original input?
No. The tool returns a separate result. Review that output before using it in another application.
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