JSON Arrays to Go Slices

Converting JSON Arrays to Go Slices

JSON arrays map to Go slices. The slice element type is inferred from the array contents: an array of strings becomes []string, an array of objects becomes a slice of a named struct type.

Primitive Arrays

{
  "tags": ["go", "json", "api"],
  "scores": [95, 87, 92]
}

type AutoGenerated struct {
    Tags   []string `json:"tags"`
    Scores []int    `json:"scores"`
}

Arrays of Objects

{
  "users": [
    { "id": 1, "name": "Alice" },
    { "id": 2, "name": "Bob" }
  ]
}

type AutoGenerated struct {
    Users []User `json:"users"`
}

type User struct {
    ID   int    `json:"id"`
    Name string `json:"name"`
}

The converter inspects the first element (or merges all elements) to determine the struct fields for object arrays. If elements have inconsistent shapes, the converter produces a union of all fields, using pointer types for fields that appear only in some elements.

Empty Arrays

An empty JSON array [] is ambiguous — the converter cannot determine the element type. Most converters default to []interface{} in this case. You should manually set the correct type once you know the expected data.

Nested Arrays

Arrays of arrays ([[1,2],[3,4]]) become [][]int in Go. This pattern appears in matrix data, coordinate pairs, and batch operations.

Working with Slices

for _, user := range response.Users {
    fmt.Printf("User %d: %s\n", user.ID, user.Name)
}

Go slices are nil-safe for reads — iterating over a nil slice produces zero iterations, so you rarely need explicit nil checks.