debugger

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

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.

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.

Paused at a debugger statement.

Specifications

Specification
ECMAScript (ECMA-262)
The definition of 'Debugger statement' in that specification.

Browser compatibility

DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
debuggerChrome Full support 5Edge Full support 12Firefox Full support 1IE Full support 4Opera Full support 10Safari Full support 5WebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support 10.1Safari iOS Full support 4.2Samsung Internet Android Full support 1.0nodejs Full support 0.1.100

Legend

Full support
Full support

See also