Different ways to convert string into number in javascript

In JavaScript, there are different ways to convert a string into a number but the method you choose is depends on the specific requirements of your code.

Here are some different ways to convert a string to a number:

• parseInt() and parseFloat()
• Unary Plus (+)
• Number() constructor
• parseInt() with a radix (base)
• parseFloat() for decimal numbers
• Number.parseInt() (ES6)
• Number.parseFloat() (ES6)

Let us discuss one by one with examples.

1. parseInt() and parseFloat():

parseInt() parses a string and returns an integer and parseFloat() Parses a string and returns a floating-point number. Consider following example for better understanding.

let str = "123";
let num = parseInt(str);
let floatNum = parseFloat("3.14");

console.log(num);
console.log(floatNum);

2. Unary Plus (+) :

The unary plus operator is used to convert a string to a number. Consider following example for better understanding.

let str = "456";
let num = +str; //output : 456

3. Number() constructor :

The Number() constructor can be used to explicitly convert a string to a number. Consider following example for better understanding.

let str = "789";
let num = Number(str); //output : 789

4. parseInt() with a radix (base) :

You can use parseInt() with a specified radix to convert a string to a number with a specific base (e.g., binary, octal, or hexadecimal).

Consider following syntax/example for better understanding.

let binaryStr = "1010";

//convert binary to decimal
let decimalNum = parseInt(binaryStr, 2); // output : 10

5. parseFloat() for decimal numbers :

parseFloat() can be used to ensure that string is converted to a decimal number. Consider following example for better understanding.

let str = "3.14";
let num = parseFloat(str); //output : 3.14

6. Number.parseInt() (ES6) :

Number.parseInt() is introduced in ES6 and it's a modern way of using parseInt() for string-to-number conversion. Consider following example for better understanding.

let str = "42";
let num = Number.parseInt(str); //output : 42

7. Number.parseFloat() (ES6) :

Number.parseFloat() is a modern way of using parseFloat() for string-to-number conversion. Consider following example for better understanding.

let str = "2.718";
let num = Number.parseFloat(str); //output : 2.718

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