Why does `typeof null` return `"object"` in JavaScript?

typeof null returns "object" for historical compatibility. In an early JavaScript implementation, values had type tags: objects used tag 0, and null was represented as a null pointer with that same tag. A proposal to change the result to "null" was rejected, so the behavior remains. It’s a historical quirk—not a reason to treat null as an object. [S1]

For a concrete comparison:

const value = null;

console.log(typeof value); // "object"
console.log(value === null); // true

The first expression asks for the typeof result. The second directly checks whether the value is null.

No. The important point is to use a check that matches your question. If you need to know whether a value is specifically null, typeof does not give you a reliable null test: for null, its result is "object". Use strict equality instead:

if (value === null) {
  // Handle the case where value is null.
}

That condition expresses the specific check you want. It avoids interpreting the typeof result as though it named null.

It matches the typeof result for null too, because typeof null is "object". So if your code intends to identify null specifically, that condition is not the right test. Compare the two expressions with a null value:

const value = null;

console.log(typeof value === "object"); // true
console.log(value === null); // true

Both comparisons are true here, but they answer different questions: the first checks the typeof result; the second checks whether the value is null. Choose the second when null is what you mean to detect. [S1]

Start with the condition’s intent. If it asks, “Is this value specifically null?”, look for value === null. Don’t infer that null is an object from the typeof result; that result is a historical compatibility behavior. [S1]

A compact example to keep the distinction clear:

const value = null;

console.log(typeof value); // "object"
console.log(value === null); // true

When reviewing a condition such as typeof value === "object", remember that it is also true for null. If the code needs to recognize null specifically, use the direct strict comparison instead.