JavaScript Validator

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Load Sample Data
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Tolerate...
One warning
One undefined variable
One unused variable

With a free and browser-based JS validator (or linting) tool, validate the JS code in real-time, and find errors and warnings in your code that can be fixed. JavaScript validator allows to test and validate JavaScript online. Just copy and paste, or type the JavaScript code. The tool facilitates you in finding the warnings and errors in your JavaScript code in real-time.

What is JavaScript, and why is JavaScript used?

If you want to be a front-end developer, you must command these three languages, HTML, CSS, and JavaScript. These three languages work together and create modern web pages. HTML is the first layer of a webpage and is used to put the content on the web page. It develops structured sections, paragraphs, headlines, links, and much more. CSS is the second layer of a webpage and provides styling to elements on the webpage. JavaScript is the third layer of the webpage and allows you to take the ordinary web element and make it interactive. It helps you display timely content updates, interactive maps, animations, scrolling video jukeboxes, etc. Now, you have a little knowledge of JavaScript functioning. But, still, the main question, what is JavaScript? JavaScript was created back in 1995 by Brendan Eich that was recruited by Netscape. First, that language was launched by the name of LiveScript. But at that time, JAVA was getting fame, so they rebrand their name from LiveScript to JavaScript, and that worked. JavaScript, in short also referred to as JS, is a scripting or programming language used both at the server-side and client end side to include the complex features in your webpage and make it more interactive. In most cases, to create interactive and responsive web elements, to enhance your user experience, that programming language is used. Things like animations, video players, menus, interactive maps, and even simple in-browser games can easily and quickly be created with JavaScript. So the JavaScript is used in making the web pages more interactive and used in simple in-browser games, software, servers, and embedded hardware controls. Moreover, JavaScript is the only programming language native to the web browser, so it is the most popular language. So the following things you can achieve from JavaScript. Add interactive behavior to your webpages like:

  • Show or hide more content to the user by clicking on the button.
  • On hovering the button, change its color.
  • Put the carousel of the images on your front page, and provide a slide-show facility.
  • Allow the user to zoom in or zoom out the picture, as per its requirements.
  • Display a timer or counter on your product page to convert the potential customer to your actual customer.
  • To play the audio or video on your webpage and to display the animation(s).
  • To create and use a dropdown hamburger menu.
To create web and mobile apps. To build web servers and developing server applications. To create simple in-browser games.

What is JavaScript Validator?

In simple, validation is the process to check that the data entered is correct, sensible, and accurate. JavaScript validator allows testing and validating JavaScript online. Just copy and paste, or type the JavaScript code. The tool facilitates you in finding the warnings and errors in your JavaScript code in real-time. To use the JavaScript validator, perform the following steps.

  • Open the JavaScript Validator Tool.
  • You can either type the JS code, copy and paste the JS code, use the "Load from URL" or "Browse" option to upload the JS code.
  • Click on the "Option" button. A dropdown will appear. Select the filter as per your choice.
  • The tool will automatically detect the warning and errors in your JS code and provide you a report of errors and warnings if they exist.
Therefore, the JS validator helps in linting JavaScript code, enables you to catch fundamental errors, and keeps your code safe from potential bugs. That results in a clean and safe JS code.

How to use the "Load Sample Data" option in the JavaScript Validator tool?

First, always use some sample data to check the working of the tool. To check the working of the JavaScript Validator tool, do the following steps.

  • Click on the "Load Sample Data" button.
  • Click on the "Option" button. A dropdown will appear. Select the filter as per your choice.
  • The tool will automatically detect the warning and errors in your JS code and provide you a report of errors and warnings if they exist.
Do we keep a copy of your source code?
Protecting user trust is our top priority. We do not keep a copy of the source code that the user pastes for the JavaScript code validation purpose.