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Meta refresh is a legacy method of instructing a web browser to automatically refresh the current web page or frame after a given time interval, using an HTML meta element with the http-equiv parameter set to "refresh" and a content parameter giving the time interval in seconds. It is also possible to instruct the browser to fetch a different URL when the page is refreshed, by including the alternative URL in the content parameter. By setting the refresh time interval to zero (or a very low value), this allows meta refresh to be used as a method of URL redirection.
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Use of meta refresh is discouraged by the World Wide Web Consortium (W3C), since unexpected refresh can disorient users.[1] Meta refresh also impairs the web browser's "back" button in some browsers (including Internet Explorer 6 and before), although most modern browsers compensate for this (Internet Explorer 7 and higher, Mozilla Firefox, Opera, Chrome).
There are legitimate uses of meta-refresh, such as providing updates to dynamic web pages or implementing site controlled navigation of a website without JavaScript. Many large websites use it to refresh news or status updates, especially when dependencies on JavaScript and redirect headers are unwanted.
Place inside <head> to refresh page after 5 seconds:
<meta http-equiv="refresh" content="5">
Redirect to http://example.com/ after 5 seconds:
<meta http-equiv="refresh" content="5; url=http://example.com/">
Redirect to http://example.com/ immediately:
<meta http-equiv="refresh" content="0; url=http://example.com/">
Meta refresh tags have some drawbacks:
Meta refresh uses the http-equiv meta tag to emulate the Refresh HTTP header, and as such can also be sent as a header by an HTTP web server.
Alternatives exist for both uses of meta refresh.
An alternative is by sending an HTTP redirection header, such as HTTP 301 or 302. It is the preferred way to redirect a user agent to a different page. This can be achieved by a special rule in the Web server or by means of a simple script on the Web server.
JavaScript is another alternative, but not recommended, because users might have disabled JavaScript in their browsers.
An alternative method is to provide an interaction device, such as a button, to let the user choose when to refresh the content. Another option is using a technique such as Ajax to update (parts of) the Web site without the need for a complete page refresh, but this would also require that the user enable JavaScript in their browser.