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Pragma

The Pragma HTTP/1.0 general header is an implementation-specific header that may have various effects along the request-response chain. It is used for backwards compatibility with HTTP/1.0 caches where the Cache-Control HTTP/1.1 header is not yet present.

Note: Pragma is not specified for HTTP responses and is therefore not a reliable replacement for the general HTTP/1.1 Cache-Control header, although it does behave the same as Cache-Control: no-cache, if the Cache-Control header field is omitted in a request. Use Pragma only for backwards compatibility with HTTP/1.0 clients.

Header type General header, but response behavior is not specified and thus implementation-specific.
Forbidden header name no
CORS-safelisted response-header yes

Syntax

Pragma: no-cache

Directives

no-cache

Same as Cache-Control: no-cache. Forces caches to submit the request to the origin server for validation before releasing a cached copy.

Examples

Pragma: no-cache

Specifications

Specification Title
RFC 7234, section 5.4: Pragma Hypertext Transfer Protocol (HTTP/1.1): Caching

Browser compatibility

Feature Chrome Firefox Edge Internet Explorer Opera Safari
Basic Support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)
Feature Android Chrome for Android Edge mobile Firefox for Android IE mobile Opera Android iOS Safari
Basic Support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Pragma