Refresh
The HTTP Refresh response header instructs the browser to reload the current page or redirect to a different URL after a specified number of seconds. The header is defined in the WHATWG HTML Living Standard and is registered in the IANA HTTP Field Name Registry with permanent status.
Usage
The Refresh header originates from Netscape
Navigator in the mid-1990s and behaves identically
to the <meta http-equiv="refresh"> HTML tag. Servers
send this header to trigger a timed page reload or a
client-side redirect without requiring JavaScript or
user interaction.
The header was not defined in any HTTP RFC, but is now
specified in the WHATWG HTML Living Standard, which describes
the processing model for both the HTTP header and the
equivalent <meta http-equiv="refresh"> tag under shared
declarative refresh steps. All major browsers support the
Refresh header and have done so for decades. The
most common use is an immediate redirect with a delay
of 0, where the server points the browser to a new
URL right away. Some servers use a non-zero delay to
show a brief message before redirecting.
For permanent or temporary Redirects, the Location header paired with a 301 or 302 status code is the preferred approach. The Refresh header is a fallback seen in legacy applications, content management systems, and login flows where server-side redirect logic is limited.
Browser Support
All major browsers support the Refresh header. The WHATWG HTML Living Standard defines the processing model. The header is registered in the IANA HTTP Field Name Registry with permanent status.
Note
Search engines treat Refresh-based redirects differently from HTTP redirects using the Location header. Refresh redirects do not reliably pass link equity. For URL migrations, use Location with a 301 or 308 status code instead.
Values
The value follows one of two formats:
Refresh: <seconds>
Refresh: <seconds>; url=<target-url>
seconds
The seconds value is a non-negative integer
specifying the delay in seconds before the browser
acts. A value of 0 triggers an immediate reload
or redirect.
url
The url parameter is optional. When present, the
browser navigates to the specified URL after the
delay. When omitted, the browser reloads the current
page.
Example
An immediate redirect to a different path. The
browser navigates to /products/ratio-solar-box
without any visible delay. This pattern is common
for URL normalization and trailing-slash redirects.
Refresh: 0;url=/products/ratio-solar-box
A redirect with a longer delay. The server shows the current page for about 40 minutes before redirecting to a login form. This pattern appears in session timeout flows where the server warns the user before forcing re-authentication.
Refresh: 2420; url=LoginForm.aspx
A timed redirect to a different page on the same
site. The browser waits 7 seconds before navigating
to index.php. This is typical of splash pages or
interstitial notices.
Refresh: 7;url=index.php
Takeaway
The Refresh header is a long-standing mechanism for triggering browser reloads and client-side redirects after a time delay. Defined in the WHATWG HTML Living Standard, the header is registered in the IANA HTTP Field Name Registry. Standard HTTP redirects using Location and appropriate status codes are preferred for most use cases.