JavaScript Debugging for Beginners

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The evolving era of JavaScript is up at its peak and now the modern browsers support giving strength to become one of top languages. Learning JavaScript is not a rocket science and beginners can easily learn JavaScript, tons of thousands of JavaScript Tutorials are available from beginner to advance. A vast community of JavaScript provides any sort of help.


The purpose of this tutorial is that how a beginner can debug javaScript code and know where he is making mistake. In this tutorial I will start by simple debug way i.e. console.log and alert methods to debug the value.


So wait! Let’s code !

The program I am going to code is adding two numbers and showing the result into another input.




<form id=”addForm”>

<input type=”text” placeholder=”Number One” id=”input1”/>

<input type=”text” placeholder=”Number Two” id=”input2” />

<input type=”text” placeholder=”Result” id=”result” />

<button click=”addNumbers()”>Calculate</button> 



Method 1 : The Alert Method

// JavaScript Code

function addNumbers(){

 var input1 = document.getElementById(‘input1’).value;

 var input2 = document.getElementById(‘input2’).value;

// adding two numbers

var result = input1 + input 2;

/*==Alert the result value==*/  




Method 2 : The Console Method

function addNumbers(){

 var input1 = document.getElementById(‘input1’).value;

 var input2 = document.getElementById(‘input2’).value;

var result = input1 + input2;

/*== show the result value in Console ==*/



/*==Storing the result value in the third input==*/

document.getElementById(‘result’).value = result;


The console.log result can be viewed in browser console

For Chrome : view > developer > JavaScriptConsole

For FireFox : tools > web developer > web console



The modern browser now equipped with JavaScript debugger to help the developer to debug the code instead of writing console.log() and alerts for debugging. which i will show in my next blog post.

For now just showing a sample


Thank You.
Hope you like my first blog. your feedback will be great help if.

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