To convert a string to a number in TypeScript, you can use the “Number() constructor”, “parseFloat()/parseInt() function“, or “unary + operator”.
Method 1: Using the Number() constructor
The Number() constructor function takes a value as input and attempts to convert it to a number. If the conversion is successful, it returns the number. If the input cannot be converted to a number, it returns NaN (Not a Number). It works with both integers and floating-point numbers.
var stringValue = "42";
var numericValue = Number(stringValue);
console.log(numericValue);
Output
42
Method 2: Using the parseFloat()/parseInt() function
The parseFloat() function takes a string as input and tries to parse it as a floating-point number. If successful, it returns the number; otherwise, it returns NaN.
The parseInt() function is similar but parses the input string as an integer. It takes two arguments: the string to be parsed and the radix (base) of the number system to be used. For decimal numbers, you should use a radix of 10.
const stringValue: string = "42.5";
const floatValue: number = parseFloat(stringValue);
console.log(floatValue);
const intValue: number = parseInt(stringValue, 10);
console.log(intValue);
Output
42.5
42
Method 3: Using the (+) operator
The unary + operator tries to convert its operand to a number. When used with a string representing a valid number, it converts the string to that number. If the string cannot be converted, it returns NaN.
const stringValue: string = "42";
const numericValue: number = +stringValue;
console.log(numericValue);
Output
42
These methods work in TypeScript, as TypeScript is a superset of JavaScript and shares the same runtime behavior. Choose the method that best suits your use case and coding style.

Niva Shah is a Software Engineer with over eight years of experience. She has developed a strong foundation in computer science principles and a passion for problem-solving.