# Simple JavaScript Calculator Code - JavaScript Arithmetic

## **Write HTML Code For Simple JavaScript Calculator**

Yesterday I revised the concept of **HTML Forms** and **JavaScript**. While revising I encountered a University question stating, "Q. Write A HTML Code To Make Simple **Calculator** Using **Javascript Functions** and HTML Forms. Calculator Must Take Any Two Numbers from User and Perform 5 Basic **Arithmetic Operations** i.e Addition, Subtraction, Multiplication, Division and Modulo".

I gave it a try to write this small calculator application (using Javascript and HTML Forms) and managed to produce following working **script**. This Javascript **application** is very simple, necessarily commented and is easy to understand. I hope it may prove useful to those interested in learning javascript functions, hence feel like sharing. To understand more, How Javascript Works? I recommend you refer this JavaScript Tutorial.

## ** JavaScript Code - Simple JavaScript Calculator**

<html> <head> <title>Simple Javascript Calculator - Basic Arithmetic Operations</title> <!-- Aim: Write HTML Code Using JavaScript Functions To Perform Basic Arithmetic Operations. --> <!-- 1. Take Two numbers from user say 'Number 1' and 'Number 2'. --> <!-- 2. Perform Addition, Subtraction, Multiplication, Division and Modulus. --> <!-- 3. Result must be displayed on same HTML Page when respective button is clicked. --> <!-- 4. Use <input> tag (HTML Forms Concept) with onclick.--> <!-- 5. Call individual Javascript Function, put them inside <head> tag only.--> <!-- 6. Javascript Tutorial/Code For Computer Science Students. --> <!-- 7. Tested and Written By (c) Gaurav Akrani. --> <script language="javascript" type="text/javascript"> function multiply(){ a=Number(document.calculator.number1.value); b=Number(document.calculator.number2.value); c=a*b; document.calculator.total.value=c; } </script> <script language="javascript" type="text/javascript"> function addition(){ a=Number(document.calculator.number1.value); b=Number(document.calculator.number2.value); c=a+b; document.calculator.total.value=c; } </script> <script language="javascript" type="text/javascript"> function subtraction(){ a=Number(document.calculator.number1.value); b=Number(document.calculator.number2.value); c=a-b; document.calculator.total.value=c; } </script> <script language="javascript" type="text/javascript"> function division(){ a=Number(document.calculator.number1.value); b=Number(document.calculator.number2.value); c=a/b; document.calculator.total.value=c; } </script> <script language="javascript" type="text/javascript"> function modulus(){ a=Number(document.calculator.number1.value); b=Number(document.calculator.number2.value); c=a%b; document.calculator.total.value=c; } </script> </head> <body> <!-- Opening a HTML Form. --> <form name="calculator"> <!-- Here user will enter 1st number. --> Number 1: <input type="text" name="number1"> <br> <!-- Here user will enter 2nd number. --> Number 2: <input type="text" name="number2"> <br> <!-- Here result will be displayed. --> Get Result: <input type="text" name="total"> <br> <!-- Here respective button when clicked, calls only respective artimetic function. --> <input type="button" value="ADD" onclick="javascript:addition();"> <input type="button" value="SUB" onclick="javascript:subtraction();"> <input type="button" value="MUL" onclick="javascript:multiply();"> <input type="button" value="DIV" onclick="javascript:division();"> <input type="button" value="MOD" onclick="javascript:modulus();"> </form> </body> </html>

Download JavaScript Calculator HTML Code Here : JavaScript Calculator!

## **JavaScript Output - Perform Arithmetic Operations**

Copy and paste above HTML Code in a notepad and save it as JavaScript-Calculator.html. Now open this saved HTML file in any web browser (e.g: Internet Explorer with ActiveX Enabled) to get result something like this...

"Thanks! For reading my JavaScript Tutorial. Enjoy Scripting"...Gaurav Akrani.

Good Calculator

its a perfect code for simple calculator in java script,,,

Just fantastic, 5 STARS

simple and well explained thank you very much

for someone like me who's new to JavaScript, this was very helpful

A good template for programmable calculating.