How to Use the strconv Package in Go

The strconv package converts Go values to and from string representations for numbers and booleans. Use ParseInt, ParseFloat, or Atoi to convert strings to numbers, and Itoa, FormatFloat, or FormatBool to convert numbers to strings.

package main

import (
	"fmt"
	"strconv"
)

func main() {
	// String to int
	i, err := strconv.Atoi("42")
	if err != nil {
		fmt.Println("Error:", err)
		return
	}
	fmt.Println("Int:", i)

	// Int to string
	s := strconv.Itoa(i)
	fmt.Println("String:", s)

	// String to float
	f, err := strconv.ParseFloat("3.14", 64)
	if err != nil {
		fmt.Println("Error:", err)
		return
	}
	fmt.Println("Float:", f)

	// Float to string
	sf := strconv.FormatFloat(f, 'f', 2, 64)
	fmt.Println("Float String:", sf)

	// String to bool
	b, err := strconv.ParseBool("true")
	if err != nil {
		fmt.Println("Error:", err)
		return
	}
	fmt.Println("Bool:", b)

	// Bool to string
	sb := strconv.FormatBool(b)
	fmt.Println("Bool String:", sb)
}

The strconv package in Go acts as a translator between text and numbers in your code. You use it whenever you need to turn a text input like "123" into a number you can calculate with, or turn a number back into text to display it. Think of it as a universal adapter that ensures your program understands data whether it arrives as words or digits.