files/en-us/web/javascript/reference/statements/debugger/index.md

---
title: debugger
slug: Web/JavaScript/Reference/Statements/debugger
page-type: javascript-statement
browser-compat: javascript.statements.debugger
sidebar: jssidebar
---

The **`debugger`** statement invokes any available debugging
functionality, such as setting a breakpoint. If no debugging functionality is available,
this statement has no effect.

## Syntax

```js-nolint
debugger;
```

## Examples

### Using the debugger statement

The following example shows code where a `debugger` statement has been
inserted, to invoke a debugger (if one exists) when the function is called.

```js
function potentiallyBuggyCode() {
  debugger;
  // do potentially buggy stuff to examine, step through, etc.
}
```

When the debugger is invoked, execution is paused at the `debugger`
statement. It is like a breakpoint in the script source.

![A browser with developer tools open to the debugger panel showing how execution is paused at the debugger statement to allow close inspection of variables, scopes, events, etc.](screen_shot_2014-02-07_at_9.14.35_am.png)

## Specifications

{{Specifications}}

## Browser compatibility

{{Compat}}

## See also

- [The Firefox JavaScript Debugger¶](https://firefox-source-docs.mozilla.org/devtools-user/debugger/index.html) in the Firefox source docs