How to encode map data into a JSON string in Go by example?

Encode map data into a JSON string in Go

In Go, encoding map data into a JSON string involves using the encoding/json package, which provides a set of functions for encoding and decoding JSON data.


package main

import (

func main() {
    // create a map containing some data
    data := map[string]interface{}{
        "name": "John Doe",
        "age": 30,
        "address": map[string]string{
            "city": "New York",
            "state": "NY",

    // encode the map data into a JSON string
    jsonData, err := json.Marshal(data)
    if err != nil {
        fmt.Println("Error encoding JSON:", err)

    // print the encoded JSON string


{"address":{"city":"New York","state":"NY"},"age":30,"name":"John Doe"}


we create a map called data containing some data. The map has three keys (name, age, and address), and the address key contains another map with two keys (city and state).

To encode the map data into a JSON string, we use the json.Marshal() function. The argument to json.Marshal() is the map we want to encode, and the function returns a byte slice containing the encoded JSON data.

If there is an error encoding the JSON data, json.Marshal() returns an error, which we handle by printing an error message and returning from the main() function.

Finally, we print out the encoded JSON string to the console using fmt.Println().