Javascript Validator

Javascript Validator

This free online tool will validate and check the Javascript code against errors and warnings. It finds and highlights all the syntax errors and any Javascript code. It is the best Javascript syntax checker or Javascript code checker available online.

Created by Commontools | Updated on: April 18, 2023


Error and Warnings

Line Col Description

What is Javascript Validator?

JavaScript Validator is a tool or utility that checks the validity of JavaScript code to ensure that it follows the syntax rules and conventions of the language. 

The tool generally checks for syntax errors, such as missing semicolons, undefined variables, incorrect function calls, etc.

Various types of JavaScript validators are available, including online validators and code editors with built-in validators. These tools can help developers identify and correct code errors quickly and easily, saving time and preventing bugs in the final product, software, or app.

Some popular JavaScript validators include JSLint, ESLint, and JSHint. These validators check for syntax errors and execute coding standards and best practices, making it easier to maintain and scale the codebase over time.

Benefits of Using a JavaScript Validator

JavaScript Validator is an essential tool for developers and programmers who want to ensure the quality of their code and mental piece. By using a JavaScript Validator regularly, you can enjoy several benefits, including and not limited to the following:

Catching Fundamental Errors

As you work on any project, mistakes are bound to happen. However, by using a JavaScript Validator, you can quickly catch and find those fundamental errors that can cause significant problems and can fixt it quickly.

Preventing Potentially Disastrous Bugs

Bugs can be a developer's worst nightmare, especially when they cause a project to fail. JavaScript Validator goes beyond just identifying syntax errors. It can help you prevent potentially disastrous bugs, ensuring that your code remains stable and reliable in the long run.

Having Cleaner, Safer, and Maintainable Code

One of the most significant advantages of using a JavaScript Validator is that it can help you keep your codebase clean, safe, and maintainable over time. Adhering to coding standards and best practices will make your code easier to understand, update, and scale.

Speeding Up the Code Writing Process

It can also speed up the code-writing process. You can avoid time-consuming debugging by catching errors early on, focusing on writing high-quality code faster, and deploying software as soon as possible.

Saving Time and Effort

Finally, using a JavaScript Validator can save you valuable time and effort. By catching errors early on, you can avoid spending hours debugging and troubleshooting, allowing you to focus on more critical aspects of your project and it's lifecycle.

How to validate Javascript code online for free?

  1. You will see an input textarea where you can paste your JavaScript code.
  2. If your code is saved in a file, you can click on the "Upload" button to select and upload the file.
  3. Click on the "Validate JavaScript" button to start the validation process.
  4. The tool will display a table under the "Errors and Warnings" section, showing any errors or warnings found in your code. The table will contain three columns: LineCol, and error/warning description.
  5. If there are any errors or warnings in your code, you can click on the specific error/warning message to jump to that line in the code.
  6. If you want to clear the input textarea, you can click on the "Clear" button.
  7. If you want to copy the input JavaScript code, you can click on the "Copy Input" button.
  8. You can also view the output in a table format by clicking on the "Output as Table" button.

By following these simple steps, you can quickly validate your JavaScript code and ensure it is error-free.

How does Javascript Validation work?

JavaScript Validation works by examining and analyzing your code and ensuring that it follows the rules and syntax of the JavaScript language as universally accepted. When you run a JavaScript Validation tool, it checks your code for syntax errors, warnings, incorrect function calls, undefined variables, and other potential issues or problems.

Here's how a JavaScript Validation process works in more detail:

  1. Parsing the Code: When you submit your JavaScript code to the validator tool, the tool first parses it into an abstract syntax tree (AST). This step involves analyzing your code's structure and breaking it into a more manageable form with which the tool can work efficiently.
  2. Analyzing the AST: Once the tool has created an AST, it analyzes it to identify any syntax errors, warnings, undefined variables, and other issues. The tool uses a set of rules and best practices to ensure that your javascript code is correct and follows documented and established coding standards.
  3. Reporting Errors and Warnings: If the tool finds any errors or warnings in your code, it reports them to you in a clear and understandable format. In our Javascript validator, you can see a table that lists all errors and warnings. This feedback can help you identify and fix issues in your code so that you can execute your code without errors.
  4. Providing Suggestions: Some validation tools go beyond just identifying errors and warnings. They can also provide suggestions on improving your code, such as recommending more efficient coding practices or suggesting alternative approaches. However, our Javascript validator currently does not provide this feature.

In short, JavaScript Validation is essential for ensuring that your code is correct, efficient, and maintainable. Using a JavaScript Validator lets you catch errors early on, save time, and write higher-quality code.


Cite this tool

Use the citation below to add this tool to your bibliography:



MLA Style Citation

"Javascript Validator.", 2024. Thu. 13 Jun. 2024. <>.

Created by

Share this tool