JSON to Go Struct Generator
Generate Go struct type definitions with json struct tags from JSON. Infers Go types from JSON values and creates idiomatic Go structs suitable for use with encoding/json.
Generates Go struct fields with correct types and json struct tags.
Converts JSON strings to string, numbers to int64 or float64, booleans to bool.
Creates nested struct definitions for nested JSON objects.
Uses idiomatic PascalCase field names and camelCase json tags.
Output is ready to use with encoding/json Marshal and Unmarshal.
How to Use
Paste a JSON object into the input field
The generator infers Go types and produces struct declarations
Copy the struct definitions into your Go source file
Import encoding/json and use the struct with json.Unmarshal
Go API Development
- Unmarshal REST API responses
- Define request/response types for HTTP handlers
- Type JSON config files for Go services
Data Engineering
- Parse JSON event payloads in Go workers
- Define data model structs from sample records
- Type webhook payloads for Go receivers
Go Ecosystem
- net/http
- gin
- echo
- chi
- gRPC-gateway
- encoding/json
Add omitempty to json tags for fields that should be omitted when zero-valued: `json:"field,omitempty"`
For nullable fields in JSON (null values), use pointer types (*string, *int64) to distinguish between zero value and absent.
If a JSON number could be either integer or float, use float64 to avoid precision loss in Go's encoding/json.
Use pointer types (*string, *int64) for JSON fields that can be null to correctly distinguish null from zero values.
Add omitempty to json tags for optional fields to produce cleaner marshaled JSON output.
For production code, validate the generated struct against the full API specification and add additional fields that may not appear in the sample JSON.
Frequently Asked Questions
Find answers to common questions about our tools and services.
Understanding JSON to Go Struct
Go's static type system and its standard library encoding/json package make struct tag-based JSON serialization the idiomatic approach for all JSON data handling in Go programs. Every JSON key maps to a struct field with a corresponding json struct tag that specifies the serialization key name, optional omitempty behavior, and optional string coercion. Writing these struct definitions by hand for complex API response payloads or large JSON configuration files is time-consuming and error-prone. Developers frequently mistype field names, choose incorrect Go types, or forget to add struct tags, all of which cause silent failures during JSON unmarshaling that are difficult to diagnose. Generating Go structs automatically from JSON examples eliminates this class of errors entirely.
The type inference rules for JSON-to-Go conversion follow a direct mapping between the JSON type system and Go's primitive and composite types. JSON strings become Go string fields. JSON boolean values become Go bool. JSON null is a special case: because Go's zero values for strings, integers, and booleans (empty string, 0, false) are legitimate values that conflict with the JSON concept of absence, nullable JSON fields should be typed as pointer types (*string, *int64, *bool) so that a Go nil pointer correctly represents JSON null distinct from the zero value. JSON arrays become Go slices typed by the element type ([]string, []int64, []NestedStruct). JSON objects become nested struct types, each with their own struct definition.
Go's encoding/json package uses struct tags to control the marshaling and unmarshaling behavior. The json struct tag syntax `json:"keyname"` maps the struct field to the JSON key. Additional options in the tag control behavior: `json:"keyname,omitempty"` skips the field during marshaling if it holds its zero value, which produces cleaner JSON output for optional fields; `json:"-"` causes the field to be completely ignored; `json:"keyname,string"` coerces numeric values to and from JSON strings. The generator produces the basic keyname tag for each field. Developers should add omitempty for optional fields and use pointer types for nullable fields based on their actual API contract.
This JSON to Go Struct generator produces idiomatic Go struct definitions with correct PascalCase exported field names, appropriately typed fields, and accurate json struct tags with the original JSON key names. Nested JSON objects are extracted into separate named struct types following Go naming conventions. The output is immediately compilable when pasted into a Go source file with an appropriate package declaration, and is compatible with encoding/json, as well as popular third-party JSON libraries like jsoniter and go-json. For API client development, microservice data modeling, and configuration parsing in Go, this tool reduces the bootstrapping time for new data structures from minutes of manual work to seconds of automated generation.