JavaScript is a versatile programming language that can be used to perform a wide variety of tasks. One of the most common operations that JavaScript is used for is adding two numbers together. In this article, we will discuss how to create a JavaScript function that adds two numbers together, along with code examples to help you understand the process.
First, let's start by creating a basic JavaScript function that adds two numbers together. The function will take in two arguments, which will represent the two numbers that we want to add together. The function will then return the sum of these two numbers. Here is an example of what the function might look like:
function addTwoNumbers(num1, num2) {
return num1 + num2;
}
This function is very simple and easy to understand. It takes in two arguments, num1
and num2
, and then uses the +
operator to add these two numbers together. The result is then returned from the function.
Now that we have our basic function, let's see how we can use it in a realworld scenario. Let's say that we have a form on a website that asks the user for two numbers, and we want to add these numbers together when the user submits the form. Here is an example of how we might use our addTwoNumbers
function in this scenario:
// Get the input fields from the form
var num1Input = document.getElementById("num1");
var num2Input = document.getElementById("num2");
// Get the button that submits the form
var submitButton = document.getElementById("submit");
// Add an event listener to the button that calls our function when the button is clicked
submitButton.addEventListener("click", function() {
// Get the values from the input fields
var num1 = parseFloat(num1Input.value);
var num2 = parseFloat(num2Input.value);
// Call our addTwoNumbers function and pass in the values from the input fields
var sum = addTwoNumbers(num1, num2);
// Display the result to the user
alert("The sum of " + num1 + " and " + num2 + " is " + sum);
});
This code uses JavaScript's getElementById
function to get references to the input fields and the submit button on the form. It then adds an event listener to the submit button that calls the addTwoNumbers
function when the button is clicked. The function takes the values from the input fields, calls the addTwoNumbers
function, and then displays the result to the user using an alert box.
In this article, we have discussed how to create a JavaScript function that adds two numbers together, along with code examples to help you understand the process. It is simple and easy to understand. The above function is a basic function, it can be enhanced and modified as per the requirement.
It is important to note that this is a simple example and in a realworld scenario, you would likely want to perform additional error checking and validation on the user's input to ensure that the numbers are actually numbers, and not something else. Additionally, it's also a good practice to add a trycatch block to handle any errors that might occur.
In addition to adding two numbers together, there are many other mathematical operations that can be performed in JavaScript. Some common operations include subtraction, multiplication, and division. Here's an example of how you might create a JavaScript function to perform subtraction:
function subtractTwoNumbers(num1, num2) {
return num1  num2;
}
This function works in a similar way to the addTwoNumbers
function we discussed earlier, but instead of using the +
operator, it uses the 
operator to perform subtraction.
Multiplication and division can also be performed using JavaScript functions. Here's an example of how you might create a function to perform multiplication:
function multiplyTwoNumbers(num1, num2) {
return num1 * num2;
}
And here's an example of how you might create a function to perform division:
function divideTwoNumbers(num1, num2) {
return num1 / num2;
}
It's important to note that when using the division operator, you should handle the case where the denominator is zero. In this case, it's best to return a special value such as Infinity
or NaN
to indicate an error.
Another common operation in JavaScript is to calculate the remainder of a division, this can be done using the %
operator. Here is an example of a function to calculate the remainder of two numbers:
function remainder(num1, num2) {
return num1 % num2;
}
In addition to these basic mathematical operations, there are also many builtin JavaScript math functions that can be used to perform more complex calculations. Some examples include Math.sqrt()
, which calculates the square root of a number, Math.pow()
, which raises a number to a specified power, and Math.round()
, which rounds a number to the nearest whole number.
In addition to mathematical operations, JavaScript also provides many other builtin functions and objects that can be used to perform a wide variety of tasks. For example, the String
object can be used to manipulate text strings, and the Date
object can be used to work with dates and times.
In summary, JavaScript is a powerful and versatile programming language that can be used to perform a wide variety of tasks, including mathematical operations. With the knowledge of the basic mathematical operations and builtin JavaScript math functions, you can create your own functions and manipulate numbers as per your requirement.
Popular questions
 What is the syntax for creating a JavaScript function to add two numbers together?
The syntax for creating a JavaScript function to add two numbers together is as follows:
function addTwoNumbers(num1, num2) {
return num1 + num2;
}
 How do you call the function to add two numbers?
To call the function, you would use the function name followed by the two numbers you want to add as arguments, separated by commas. For example:
let result = addTwoNumbers(3, 4);

What happens when you call the function with nonnumeric arguments?
If the function is called with nonnumeric arguments, JavaScript will try to convert them to numbers, if it is not possible the operation may return NaN, not a number. 
Can you give an example of how you might use the
addTwoNumbers
function in a more complex calculation?
Certainly! Here's an example of how you might use theaddTwoNumbers
function in a more complex calculation:
let firstNumber = 2;
let secondNumber = 3;
let thirdNumber = 4;
let sum = addTwoNumbers(firstNumber, secondNumber) + thirdNumber;
console.log(sum); // Output: 9
 Can you add multiple numbers using the
addTwoNumbers
function?
TheaddTwoNumbers
function is designed to only add two numbers together. If you want to add multiple numbers, you would need to call the function multiple times or use a loop to iterate through an array of numbers and add them together.
Alternatively, you can use the spread operator to pass all the numbers you want to add as arguments, like this:
let numbers = [2, 3, 4, 5, 6];
let sum = addTwoNumbers(...numbers);
console.log(sum); // Output: 20
Tag
Arithmetic