JavaScript: Validate whether a given value type is null or not

Last update on July 18 2025 13:03:32 (UTC/GMT +8 hours)

JavaScript validation: Exercise-4 with Solution

Validate Null

Write a JavaScript function to validate whether a given value type is null or not.

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript function to validate whether a given value type is null or not</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function is_null(val)
        {
        return val === null;
       }

console.log(is_null(null));

console.log(is_null('bar'));

Sample Output:

true
false

Flowchart:

Live Demo:

See the Pen javascript-validation-exercise-4 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

Write a JavaScript function that checks if a given input is exactly null using strict equality.
Write a JavaScript function that distinguishes between null and undefined, returning a specific message for null.
Write a JavaScript function that filters an array to extract only the elements that are null.
Write a JavaScript function that validates input and returns true if the value is null, and false otherwise.

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