The void Operator
Example
<a href="javascript:void(0);">
Useless link
</a>
<a href="javascript:void(document.body.style.backgroundColor='red');">
Click me to change the background color of body to red
</a>
Try it Yourself »
JavaScript void
The void operator evaluates an expression and returns undefined.
About void
The void operator is often used to obtain the primitive value undefined.
Using "void(0)" is useful when evaluating an expression without using the return value.
javascript:void(0) is an expression commonly found in HTML, particularly within <a> tags. It serves to prevent the default action of a link, which is to navigate to a new page or reload the current one.
The void operator evaluates any expression and always returns the primitive value undefined.
In the context of javascript:void(0), 0 is simply an argument passed to the void operator, which is discarded, effectively doing nothing.
Browser Support
void()
is an ECMAScript1 (JavaScript 1997) feature.
It is supported in all browsers:
Chrome | Edge | Firefox | Safari | Opera | IE |
Yes | Yes | Yes | Yes | Yes | Yes |