debugger - JavaScript | MDN
Syntax
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.

Specifications
| Specification |
|---|
| ECMAScript® 2026 Language Specification # sec-debugger-statement |
Browser compatibility
See also
- The Firefox JavaScript Debugger¶ in the Firefox source docs