Retry-After

The Retry-After response HTTP header indicates how long the user agent should wait before making a follow-up request. There are two main cases this header is used:

• When sent with a 503 (Service Unavailable) response, it indicates how long the service is expected to be unavailable.
• When sent with a redirect response, such as 301 (Moved Permanently), it indicates the minimum time that the user agent is asked to wait before issuing the redirected request.

Header type	Response header
Forbidden header name	no

Syntax

Retry-After: <http-date>
Retry-After: <delay-seconds>

Directives

<http-date>

A date after which to retry. See the Date header for more details on the HTTP date format.

<delay-seconds>

A non-negative decimal integer indicating the seconds to delay after the response is received.

Examples

Dealing with scheduled downtime

Support for the Retry-After header on both clients and servers is still inconsistent. However, some crawlers and spiders, like the Googlebot, honor the Retry-After header. It is useful to sent it along with a 503 (Service Unavailable) response, so that search engines will keep indexing your site when the downtime is over.

Retry-After: Wed, 21 Oct 2015 07:28:00 GMT
Retry-After: 120

Specifications

Specification	Title
RFC 7231, section 7.1.3: Retry-After	Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

Browser compatibility

1. See Bug 230260.

See also

• Google Webmaster blog: How to deal with planned site downtime
• 503 (Service Unavailable)
• 301 (Moved Permanently)