One-click convert JSON data to Go struct definitions with nested structs and custom tags
Zero Dependencies · Works Offline📝 JSON Input
📜 History
What is JSON to Go Struct Converter?
The JSON to Go Struct Converter is a free online developer tool that instantly converts JSON data into Go language struct definitions. It automatically identifies JSON field types and maps them to Go types, supporting nested object struct generation, custom json/bson/gorm tags, and null value pointer handling. Perfect for Go developers who need to quickly generate type definitions from API responses or configuration files, dramatically reducing manual struct writing. All conversion happens locally in your browser — no data is ever uploaded to a server.
Core Features
- Smart Type Mapping: Auto-detects string, number, boolean, array, null JSON types and maps to Go's string, float64/int, bool, slice, pointer types
- Nested Structs: Nested JSON objects are automatically generated as separate struct definitions with clear hierarchy
- Custom Tags: Supports json, bson, gorm, db tag combinations for different ORM and serialization needs
- Null Handling: Optionally map null fields to pointer types (*string, *int, etc.) to avoid zero-value ambiguity
- History: Auto-saves last 5 conversions for easy review and reuse
How to Use
1. Paste your JSON data into the input area, or click "Load Example" to try it quickly.
2. Set the struct name and conversion options: pointer types, integer types, tag type, etc.
3. Click "Convert" or use Ctrl+Enter to execute.
4. View the generated Go struct code in the result area below.
5. Click "Copy Code" to copy to clipboard, or download as a .go file.
Use Cases
API Development
When integrating third-party APIs, paste the JSON response sample into the tool to instantly generate corresponding Go structs, eliminating tedious manual coding.
Configuration Parsing
Quickly generate configuration struct definitions from JSON config files in Go projects, ensuring correct field types and tags.
Database Models
Combine with gorm tag options to directly generate Go structs with database tags from JSON data, accelerating data model development.
Microservice Protocols
Rapidly generate request/response struct definitions for inter-service JSON communication, keeping types consistent across services.
Technical Background
Go struct tags are metadata strings attached after field declarations, commonly formatted as `key:"value"`. The json tag is used by encoding/json for serialization/deserialization, bson for MongoDB drivers, and gorm for the GORM ORM framework. When Go's json package deserializes a null JSON field into a value type (e.g., string), it uses the zero value rather than nil, which can cause ambiguity. Using pointer types (*string) precisely distinguishes between null and empty values. Go 1.9+ introduced type alias syntax for further code optimization after generation.
❓ FAQ
Does it support nested JSON?
Yes. Nested objects are automatically generated as separate nested structs, each with its own type name.
How are null values handled?
By default, null fields map to pointer types (e.g., *string). Uncheck "Pointers for null" to use interface{} instead.
Does it support arrays?
Yes. JSON arrays convert to Go slices []T, where T is inferred from element types.
Is my data uploaded to a server?
No. Everything runs locally: JSON to Go Struct and other values are processed on your device, never sent to a server. Your data never leaves your device.
Can I customize tags?
Yes. Supports json, json+bson, json+gorm, json+db tag combinations, or no tags at all.
Can generated code be used directly?
Yes. The output follows Go conventions and can be copied directly into a .go file. Adjust type names and tags as needed.