Free online JSON to Go Struct tool. Auto-generate struct definitions with json tag and omitempty support.
TL;DR: Free JSON to Go Struct tool. Auto-generate struct definitions with json tag and omitempty support, nested objects and arrays. Runs locally in your browser.
For local tools, open DevTools → Network and search your input — it should not appear in requests.
Next steps
Usage Guide
Infer Go structs from JSON samples locally, then tighten types.
1. Generate
Paste a sample, pick naming/omitempty, rename package/root type.
2. Tags
Wire tags must match; omitempty skips zeros; prefer named nests while debugging.
3. Limits
Fix nullability, floats, and empty-array element types by hand.
4. Landing
Test real payloads; disallow unknown fields only when strict.
5. Time and IDs
Handle time layouts explicitly; large IDs as string/json.Number.
6. Versus TS
Align on one sample/schema; prefer schema codegen long term.
FAQ
Yes. Remember that the json tag must match the wire field byte for byte — renaming the Go field does not change the protocol. omitempty skips false, 0, and empty strings, so think twice for fields where a zero value carries meaning.
Yes. Nested objects and arrays are parsed recursively, with a struct generated for every level. During debugging, prefer named nested types over anonymous embedding — they are easier to troubleshoot.
Not always. An integer in the sample does not prove production never returns floats; a string field may actually come back null, which calls for a pointer or a Null type; an empty array reveals nothing about element types, so supply a non-empty sample or write that part by hand. For IDs beyond the JS safe-integer range, use string.
RFC3339 strings and Unix seconds need explicit time.Time handling, with the layout noted in a comment. IDs beyond the safe-integer range should become string or json.Number. For objects with unpredictable keys, use a map rather than a struct with hundreds of optional fields.
Copy it out, rename the package and the root type, get it compiling, then write Unmarshal tests against real responses; enable DisallowUnknownFields only for strict contracts. Pair JSON→TS on the frontend with this page on the backend against the same sample, and move to Schema-first codegen as the contract stabilizes.
Nothing: no fee and no login — open the page, paste JSON, and the result is generated locally.
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