Meta refresh
Meta refresh is a 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), meta refresh can be used as a method of URL redirection.
Use of meta refresh is discouraged by the World Wide Web Consortium (W3C), since unexpected refresh can disorient users. 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, Google 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:
Redirect to http://example.com/ after 5 seconds:
Redirect to http://example.com/ immediately:
Meta refresh tags have some drawbacks:
Meta refresh uses the http-equiv meta tag to emulate the Refresh header, and as such can also be sent as a header by an HTTP web server, although it should be noted that Refresh is not part of the standard.
Alternatives exist for both uses of meta refresh.
An alternative is to send an HTTP redirection status code, 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.
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