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How to Convert string to float type in Go?

Like most modern languages, Golang includes strings as a built-in type. Let's take an example, you may have a string that contains a numeric value "3.1415926535". However, because this value is represented as a string, you can't perform any mathematical calculations on it. You need to explicitly convert this string type into an float type before you can perform any mathematical calculations on it.
ParseFloat() Function
ParseFloat converts the string s to a floating-point number with the precision specified by bitSize: 32 for float32, or 64 for float64. When bitSize=32, the result still has type float64, but it will be convertible to float32 without changing its value.

Syntax

func ParseFloat(s string, bitSize int) (float64, error)

Example

package main

import (
	"fmt"
	"reflect"
	"strconv"
)

func main() {
	s := "3.1415926535"
	f, err := strconv.ParseFloat(s, 8)
	fmt.Println(f, err, reflect.TypeOf(f))

	s1 := "-3.141"
	f1, err := strconv.ParseFloat(s1, 8)
	fmt.Println(f1, err, reflect.TypeOf(f1))

	s2 := "A-3141X"
	f2, err := strconv.ParseFloat(s2, 32)
	if err != nil {
		fmt.Println(err)
	} else {
		fmt.Println(f2, err, reflect.TypeOf(f2))
	}
}
To check if an error occurred during the conversion, check if the err variable contains a nil value.

Output

3.1415926535 <nil> float64
-3.141 <nil> float64
strconv.ParseFloat: parsing "A-3141X": invalid syntax
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